The 35 XCB, the sledgehammer I've been waiting for

[Bjornb]

I received my first rifle chambered in 35 XCB around the middle of May, and not until now do I feel confident writing about it. Make no mistake: The cartridge is clearly a premium hunting chambering, holding slightly more powder than a .358 Winchester while sporting the long neck of a .35 Whelen.
144576144577

My rifle is a sporter built on an FN Mauser action, with a 26" Douglas barrel and a McMillan Hunter stock. A Timney trigger and a Nikon scope round out the package:
144578

I loaded and shot a few rounds rather randomly, trying to get a feel for the rifle. I even loaded up some 358009s, which had to be nose-sized (Buckshot nose sizer) so I could seat the bullet in the cartridge neck. These are samples from my first range day:
144581144582
Nothing spectacular, but the gun clearly wanted to shoot. I re-grouped and tried again:
144583
Not what I had dreamed about, and both Goodsteel and I were scratching our heads. I shipped the rifle back to Tim, and he is in the process of cutting an inch off the barrel to see if that will change the harmonics and improve accuracy. Funny thing is, before sending the rifle to me Goodsteel stabbed 7 shots in the same hole, and we were convinced we had a perfect rifle. I still think we have a perfect rifle; she just may need a little tweaking before I take her moose hunting.

Fast forward, Tim recently sent me his "Felix" target rifle so I could keep shooting (Bertha is being re-stocked and that's a time-consuming affair). He also sent along 3 barrels: A 30 inch Shilen in 35 XCB, a 26 inch Shilen in 30-06 XCB, and his own Brux in 30 XCB.

I shot the 35 XCB barrel today, had time for a short range trip and made 10 rounds each with the NOE 35 XCB bullet and the Barnes 225 X-bullet in .358. Both were loaded over 50 grains IMR4320. The load was arrived at by interpolating loads from the Sierra manual (358 Win, 35 Whelen, 35 Rem Mag). The results were encouraging, even though they need more work. Speeds were pretty good:
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Notice the first shot with jacketed (100 fps slower than the rest). Excluding this shot everything else showed really good ES and SD.

I was especially happy with the NOE bullet at speeds exceeding 2500 fps.
This gave me something to build on.

[taco650]

I realize you're searching for the best groups possible but if the groups don't get better, your moose will still be DEAD!

[bearcove]

Yep dead moose. 2-3 MOA is plenty good for moose where I've hunted them.

[velocette]

A dead moose is NOT good enough. The dead moose must be perforated in precisely the correct location with a projectile of the correct diameter, weight and speed.
Only then will the (properly terminated) dead moose be good enough.
Bjornb; Enjoy your vacation!

[Yodogsandman]

Bjornb, Sure hope you can show us how that 35XCB does on a monster moose! Good luck!

[MBTcustom]

A dead moose is NOT good enough. The dead moose must be perforated in precisely the correct location with a projectile of the correct diameter, weight and speed.
Only then will the (properly terminated) dead moose be good enough.
Bjornb; Enjoy your vacation!

Finally! Somebody who UNDERSTANDS!!!!!

[bearcove]

Finally! Somebody who UNDERSTANDS!!!!!

Should of got a 35 whelen it does just that.:kidding:

[NoAngel]

Nothing new under the sun. ;)

[MBTcustom]

It's very true there's nothing new under the sun, but saying the 9X57 is the same as the 35XCB is about as accurate as saying the 35 Remington is the same as the 358 Winchester.
Somebody, somewhere, sometime, did this cartridge and had a name for it. I call it the 35XCB because it is part of the XCB project.
I wanted a 358Winchester with a little bit more case capacity, and a Whelen style neck, and I wanted a 35 caliber bullet with a better BC for doing a long toss.

(BTW Excess650, that is a truly gorgeous rifle!)

[bearcove]

AH! Almost a 35 Whelen.

[MBTcustom]

Well, going by internal case capacity, it's almost a 358 Winchester. Going by case length, its almost a 9X57. Going by neck length, it's almost a Whelen.
It's got the same neck wall thickness as the 30-30.
The 35XCB was designed to feed flawlessly and to be a dyed in the wool hunting cartridge for Mauser rifles. I'm hoping to get one built for myself by November so I can bust a deer with it. But if that doesn't happen, I'm sure Bjorn will be stringing up much more impressive critters from Alaska.

[bearcove]

Sounds fun, I have thought for a long while, a long necked 358 would be about right.

[MBTcustom]

Sounds fun, I have thought for a long while, a long necked 358 would be about right.
Get that man a cigar!!! That's what I've got going on here!
Now, I always thought that the 358 and the 308 were just a little bit conservative on case capacity, and the 30 and 35 XCB take care of that too. When loading these two cartridges, I use 308 and 358 load data respectively. I usually figure that max data for one is starting data for its XCB counterpart.

[taco650]

Tim,

Could a 358 Win be "bored out" to 35 XCB with out re-barreling?

[MBTcustom]

Tim,

Could a 358 Win be "bored out" to 35 XCB with out re-barreling?

Fraid not. The XCB has the 30-06 shoulder diameter which is too small to clean up a 308 chamber. I had considered redesigning the 30/35XCB with a more improved 308/358 style shoulder so that 308/358's could be reamed out, but that would negate several other attributes of the cartridges.
It takes a slow twist to really realize the full potential of the cartridges anyway. I mean the RPMTH of the typical 12 twist is 2300FPS, and I can get that with a dad gum 30-30. The XCB's were bread for SPEED and accuracy.

[taco650]

Fraid not. The XCB has the 30-06 shoulder diameter which is too small to clean up a 308 chamber. I had considered redesigning the 30/35XCB with a more improved 308/358 style shoulder so that 308/358's could be reamed out, but that would negate several other attributes of the cartridges.
It takes a slow twist to really realize the full potential of the cartridges anyway. I mean the RPMTH of the typical 12 twist is 2300FPS, and I can get that with a dad gum 30-30. The XCB's were bread for SPEED and accuracy.

Ok, thanks for the info. Which twist is preferred for this one (sorry, I missed the intro)?

[MBTcustom]

I would prefer 16 twist but given the limited selection of barrel makers that have that twist, I went with 14. The 14 twist will get you to 2600FPS and definitely maintain 2MOA or less.

[Larry Gibson]

It's very true there's nothing new underthe sun, but saying the 9X57 is the same as the 35XCB is about as accurate assaying the 35 Remington is the same as the 358 Winchester.
Somebody, somewhere, sometime, did this cartridge and had a name for it. I callit the 35XCB because it is part of the XCB project.

Why such a new cartridge (1922)?. The 9x57pre-dates 1900.

I designed the cartridge quite a few years back actually. I called it the 35x57 back then. The concept was in conjunction with the 30x57 (30 XCB) which was to have a standard 8mm/'06 head size cartridge with a tapered case to feed through Mauser actions of M91 - M98 types with out an action alteration being needed. Many of those only have 3" long magazines hence the 57mm length. The case was also designed to have the 30-30/30-40/30-06 length neck for better support and alignment with cast bullets.

An additional concept was that standard or match 30-06 and 35 Whelen reamers could be used to just short chamber the barrels w/o the expense of custom reamers. The same was for dies; standard 30-06 and 35 Whelen loading dies could simply be shortened so expensive custom dies would not be needed. Easily available 8x57 or any of the '06 family of cases could easily be used to form the cases. Cases could be easily formed with the standard FL dies and simply trimmed to length.

Tim has done an outstanding job taking the concept one step further with the tighter necks and thus the excellent 30 and 35 XCB cartridges. They are ideal for use with Mauser actions but can be used with other actions ast well.

Larry Gibson

[MBTcustom]

That's the truth Larry, and thank you for letting me run with your original idea!

But the point I was making is that no matter what you do, you can find something that was similarly done by someone else to accomplish a goal they had. What really makes the XCB cartridges, bullets, casting equipment, loading equipment, and measuring equipment different is the way we are using it, and what we are achieving using these things.
The XCB project is not about doing anything new. It's about humbly pointing out what's been there the whole time but hindered by one thing or another, or not used the way it really should be in order to achieve the goal.

2 years ago, there were no sub1.5MOA, 3100FPS+,10 shot groups posted on this forum. Now there are dozens. The XCB project didn't change reality in any way shape or form, it just exposed reality for what it is, and we accepted it and are better for it. Albert Einstein was correct when he said: "Once we accept our limits, we go beyond them" and that is what we have done here.

All of the things I have done in the XCB project have been thought of, theorized, postulated, dreamed about, written about, and hinted about by other people long before I was born. I take little credit for these ideas even if I just happened to use my own common sense to come to the same conclusions. All I did was decide I was going to make it happen. I grabbed a rope and started pulling. Lots of others came to help me and I hope others will too, but I'll keep pulling until I get where I want to go with the XCB project.
There is still a lot to learn.

[Larry Gibson]

"no matter what you do, you can find something that was similarly done by someone else to accomplish a goal they had."

I certainly concur with that as the 35x57 I came up with was meant to be ballistically the same or close to it as the 358W or the 9x57. What was different about the 35x57 is it was designed to;

have a case taper to fit Mauser actions and feed reliably w/o action alteration.

to have a case neck of 30-06 or 35 Whelen length.

to use standard readily and commonly available reamers to chamber a new barrel with.

To use standard and readily available common dies w/o resorting to expensive dies or custom dies.

to use readily available common cases to easily form cases w/0 extensive equipment.

The 30x57 and the 35x57 both meet all of these requirements. The cases for both cartridges are easily formed with the standard, shortened FL die that comes with standard 30-06 and 35 Whelen dies, especially if a standard RCBS dies set is used. If 8x57 cases are used case trimming is many times not even necessary. Neither of those cartridges would even require neck turning if a standard or match reamer is used.

The .308W, the 9x57 nor any other wildcat cartridges meet all of those requirements. The 30x57 and 35x57 do meet those requirements. That's why I designed those two cartridges that way. The other benefits of higher velocity with cast bullets was a result of postulation of using slower twists to keep the RPM in check as Tim suggests. I was correct in that postulation and many thanks to Tim for his impetus in moving us forward with the 30 XCB past what I was doing with my 14" twist .308W Palma rifle. Tim deserves a lot of credit for the progress we have made. Yes there is still a lot to learn about shooting cast bullets at HV and we are still learning.

Larry Gibson

[taco650]

Neck wall thickness has been mentioned here and I'm still not understanding what its importance is. I followed the 30XCB project for a while until... Can someone please explain the neck wall thing?

[MBTcustom]

In my opinion, the neck thickness being thin like the 30-30 is a boon in that it has less ability to deform the bullet, or apply different tensions on it, so release of the bullet to the barrel is very consistent.
Also, having the neck fit the chamber with a .0003 slip fit can be an advantage in some cases by helping to support the bullet as it is engraved to the rifling.

[Larry Gibson]

Also if the neck is of equal thickness it's entire length and is a good fit to the chamber neck it helps keep the bullet concentric with the bore as the bullet is pushed forward into the throat/bore.

Larry Gibson

[taco650]

Tim/Larry,

Thanks for the explanations, they make sense.

[TXGunNut]

Tim, please get to work on Bjornb's rifle.[smilie=s: I think he's onto something and I'm really curious about what he has planned. Besides, I need to send you the old levergun we talked about awhile back and I don't want you messing with it until you get Bjornb's new hunting rig up and running. ;-) I probably won't get to hunt with the 35XCB boolit this year in my 35 Whelen but I'm very interested in what you guys are doing.

[MBTcustom]

Tim, please get to work on Bjornb's rifle.[smilie=s: I think he's onto something and I'm really curious about what he has planned. Besides, I need to send you the old levergun we talked about awhile back and I don't want you messing with it until you get Bjornb's new hunting rig up and running. ;-) I probably won't get to hunt with the 35XCB boolit this year in my 35 Whelen but I'm very interested in what you guys are doing.

Not to worry, I was able to complete his rifle just before my VFD bit the dust. Now I'm catching up on a bit of handwork that needs tending to while I'm waiting for the new unit to arrive. It's nice actually. Machinery is a huge help, but sometimes I wonder if I start to think more of it in my mind than it actually is. I've been blackening metal with a kerosene soot and scraping wood the last few days and that's just good work. I love watching metal sink into wood over the course of an hour.

[dragon813gt]

I hope the VFD isn't to far out. We've been waiting over three weeks for a few of them at work. They don't keep a stock of them on hand :(

[taco650]

I hope the VFD isn't to far out. We've been waiting over three weeks for a few of them at work. They don't keep a stock of them on hand :(

VFD bit? An item for the milling machine?

[Hannibal]

Variable Frequency Drive. One of several options for running equipment with 3-phase electric motors in locations where only 220 V power is available.

[MBTcustom]

Good news is the VFD showed up today, and lars45 was good enough to drive over and help me with getting it installed correctly. Times like this, I'm real thankful for castboolits and the friends I've made through this site, especially Glenn and Leah with WLL! Solid gold folks!
We're going to have to get after it again, but I think Glenn learned how to translate oriental to southernees via the loosely translated instruction manual. [smilie=b:

[runfiverun]

how'd he pull that off with an Idaho accent? :lol:

[dragon813gt]

Variable Frequency Drive. One of several options for running equipment with 3-phase electric motors in locations where only 220 V power is available.

Or in most cases installed on three phase equipment to vary the motor speed. Only home mechanics use them to power three phase motors w/ single phase supply. The ones I need are for large Carrier package units. Current drives have screwed up boards that aren't outputting a clean sine wave on the low end so the drive is locking out on over current faults. You should see the motors shake when they do this :mad:

[taco650]

Variable Frequency Drive. One of several options for running equipment with 3-phase electric motors in locations where only 220 V power is available.

Ok, thanks for the explanations. I've heard them called a roto-phase. Anyway, sorry for the tangent so lets get back to the 35XCB project!

[Bjornb]

Been very busy all summer trying to develop a cast hunting load for the 35XCB. I really wanted to shoot the NOE 358009, so that's where I have concentrated my efforts. I had a quantity of these bullets from shooting a .358 Winchester a while back; these bullets were cast rather hard from Lino/range scrap and lubed with 2500+. As shown in the OP, these shot pretty well over a mild load of 2400, at just over 1300 fps.

Trying to push these bullets really fast proved impossible for this shooter. I changed alloy (Goodsteel sent me a box of bullets cast from his House Alloy, air cooled) and had them going at 2250 fps, using 41 grains IMR3031. They grouped around 5 inches. Continuing the experiment i backed off to 35 grains (1950 fps) and finally got sub-2 MOA at 100 yards. Not the speed I wanted, but one I could live with.

At this point I cast up a quantity of the 358009 in COWW+2%Sn, mixed 50/50 with pure lead, air cooled. I figured this would be an excellent expanding alloy for moose, and I was not expecting to be taking any shots beyond 200 yards. Testing this new alloy at my local 100-yard range, everything looked fine; consistent groups in the "just below 2 inch" range.

Today I took this combination to a 200-yard range, and that's where it all fell apart. While still shooting fine at 100 yards, it would open up to 6-8 inches at 200.

So I'm back at square one with my hunting load. I have a backup plan with jacketed (the Barnes 225X shoots great), but cast is where my heart is.
There's always the NOE/RCBS 200 FN, but time's getting short.

[taco650]

Would Trailboss or 5744 be a better choice for accuracy? I know they won't get the speed you desire but...

[Bjornb]

Yeah 5744 would probably shoot just fine, just as 2400 does. Those are tried and true standbys that work most of the time. Trailboss is a powder I haven't tried much.
I have a few more weeks to experiment and I'll share any progress. What baffled me the most was that the load that shot well at 100 yards fell apart at 200. And this was a load that wasn't particularly fast. Back to the drawing board.

[runfiverun]

yep...

[1johnlb]

Perhaps, the spin from the slow twist at that speed, isn't enough to keep the bullet stabile out to 200.

[MBTcustom]

Perhaps, the spin from the slow twist at that speed, isn't enough to keep the bullet stabile out to 200.

To tell you the truth, I'm not so sure 14 is really all that "slow" for a 35. Experiments are in the works.

[1johnlb]

To tell you the truth, I'm not so sure 14 is really all that "slow" for a 35. Experiments are in the works.

Your right, I forgot what thread I was on, 35xcb. I was thinking the 17 he's been shooting with the 30xcb, my bad.

[Yodogsandman]

In post#1, 50gr of IMR4320 with the 35XCB boolit looked like it was close. I really thought that with a few tweaks, you'd have "the load". Have you tried powders on both sides of it on the burn chart?

[35 shooter]

Bjornb this probably won't help you a bit, but in the 35 whelen with the 358009 i wound up just barely kissing the lands on the nose for best results . I started with .151" engagement and could only get 2" 5 and 10 shot groups @ 100 yds. with it.
I really had to play with seating depth on that boolit and the more i backed off the better it got.

I have no idea if your chamber will allow you to go shorter or how you have it seated...just saying what worked for me. It worked out to avg. 1" @ 100yds. sometimes just under, sometimes just over. My load is just over 2200 fps.

I'm going through the same thing now with the 35xcb. It does not like engagement in my rifle at all. I'll try backing off and giving it a run at the rifling next.
Playing with the seating depth with that 358009 might help...it did for me, but i almost gave up on it first. Now it's one of my most accurate boolits in the whelen.

Good luck with it.

[runfiverun]

has anybody captured any of these boolits and examined them for trailing edge failure?
or looked at the depth relationships of the rifling.
or measured for set-back.?

something is waay off here, even in a 14 twist rifle 19-20 hundred fps should shoot well.

[Bjornb]

In post#1, 50gr of IMR4320 with the 35XCB boolit looked like it was close. I really thought that with a few tweaks, you'd have "the load". Have you tried powders on both sides of it on the burn chart?

That's correct, the 4320 load was excellent and very fast. My problems arose when I veered off into HUNTING type bullets. This meant casting softer bullets and also shooting blunt bullets, e.g. the RCBS/NOE 200 FN or the 358009. I'm now looking into drilling a small HP in the 35XCB bullet and using it for hunting, cast from Lyman #2. Not sure it's the right way to go, but I'm mulling it over with Goodsteel.

[Bjornb]

Bjornb this probably won't help you a bit, but in the 35 whelen with the 358009 i wound up just barely kissing the lands on the nose for best results . I started with .151" engagement and could only get 2" 5 and 10 shot groups @ 100 yds. with it.
I really had to play with seating depth on that boolit and the more i backed off the better it got.

I have no idea if your chamber will allow you to go shorter or how you have it seated...just saying what worked for me. It worked out to avg. 1" @ 100yds. sometimes just under, sometimes just over. My load is just over 2200 fps.

I'm going through the same thing now with the 35xcb. It does not like engagement in my rifle at all. I'll try backing off and giving it a run at the rifling next.
Playing with the seating depth with that 358009 might help...it did for me, but i almost gave up on it first. Now it's one of my most accurate boolits in the whelen.

Good luck with it.

Here's what I had to do to load the 358009: Since the bullet cast the nose at .3515 or thereabouts, I used a Buckshot nose sizer with a .350 bushing to get the long nose down to bore size, and then I loaded the bullet like a bore rider, with a seating depth of only about .300 inches. Otherwise it would have had the gas check below the neck, something I wanted to avoid. Maybe this is what caused the problems.

[Bjornb]

has anybody captured any of these boolits and examined them for trailing edge failure?
or looked at the depth relationships of the rifling.
or measured for set-back.?

something is waay off here, even in a 14 twist rifle 19-20 hundred fps should shoot well.

No, I wasn't able to recover any bullets. What puzzled me the most was that I'd get tight groups at 100 yards but only spray-n-pray at 200.

[runfiverun]

a super close look at group shape, and the holes themselves could also provide a clue.

[taco650]

Would HP'ing the XCB change the fight characteristics?

[oldblinddog]

a super close look at group shape, and the holes themselves could also provide a clue.

^^^^^
this ;)

[Hamish]

a super close look at group shape, and the holes themselves could also provide a clue.

Run, what would be your diagnosis?

Not calling you out, but seeing these kind of "Read the tea leaves." kind of posts by more experienced cast shooters have always bothered me as they give no clue to anyone not already versed in whatever is being discussed. It's nice shorthand for conducting a private discussion among those already in the know, but leaves anyone else completely in the dark, and as the 35 XCB would seem to be having trouble gaining the same kind of initial success that the 30 XCB did, this would seem to be the perfect thread for that kind of diagnostic discussion.

[Bjornb]

Hamish,
I completely agree with your "read the tea leaves" statement. Cryptic comments like the one in r5r's post above makes me scratch my head. I am NOT a life long cast bullet shooter, and I need all the help I can get.

Specifically in this case the group shapes are no different than what I have seen numerous times while shooting cast and jacketed side by side. Jacketed tends to show more "controlled" groups, something I suspect occurs due to the better uniformity of the projectiles themselves. No gas checks or lube, harder bullets and so on.

As for the initial success of the 35XCB, let me just give a quick synopsis of the completely different approach that was taken with the 2 cartridges:

-The 30XCB was a joint project that started a long time before I was ever a member of this forum. Many current and former members collaborated, and the project benefited from a wealth of shooting trials by those involved (example: Larry Gibson had already completed many HV shooting trials using .308W rifles and a number of bullet designs that we were able to quickly duplicate in the 30 XCB rifles, cartridge and bullet design).

-The 35XCB currently exists only in my gun safe: I own 2 rifles. I have about 150 fire formed cases, and Tim Malcolm has maybe 20. Add to that the fact that ever since I started shooting the cartridge (in May of this year), I have spent most of my energy trying to develop a hard-hitting and reasonably accurate hunting load, and there has been preciously little time spent on velocity trials and accuracy shooting in the bench rifle.

At this point Tim is getting close to finishing his own rifle chambered in 35XCB; that will bring more data to the table.

The NOE 35XCB bullet is showing a lot of promise, but it has not yet been cast in the large number of alloys that I used for the 30XCB project, and it's therefore difficult to draw good conclusions.

So don't touch that remote, more news will be forthcoming. Maybe as soon as this weekend.

[taco650]

Bjornb,

I can only speak for myself when I say "I'm waiting with baited breath" for more info on your (& Tim's) results. I've been thinking about converting my old 30-06 to 35 Whelen but if the 35XCB works better and uses less powder in the process, I may go that route.

[cainttype]

Bjorn, if you're confident that shooter error isn't involved (and I'm sure you've eliminated the majority of that), the 200 yd holes might provide evidence of a stability issue by displaying even minor elongation.
A recovered projectile with inconsistant lube residue remaining could open groups without elongating holes.
You're already familiar with stringing issues, both verticle and horizontal.

If you want to use the test alloy, I'd probably try shooting these heavies without nose-sizing, even if the GC seats slightly lower than the neck, with some of the slowest powders you have that can bring the velocities near where you want. Deep-seated GCs aren't necessarily bad, and the extra nose support might prove to be an advantage.
I'd want to try to recover some of the casts in order to insure there isn't any lube chunks causing issues with balance.
If your impact holes display any tipping, I would attempt to increase velocities if possible. Low velocities and slow twist-rates may not be the problem, but it never hurts to keep those possibilities in mind.

[Bjornb]

I removed the scope this morning in order to try a different one (the only variable I could think of that hadn't been addressed). The rear scope mount (Leupold style) had caught one of the lateral adjustment screws at an angle and was definitely not tightened down the correct way.

Regardless, I installed new rings and also moved my large Weaver T36 scope over to the hunting rifle (it's a known quantity). On Saturday I plan to shoot the 2 loads that shot well in the bench rifle (50 grs. IMR4320 under both the Barnes 225 and the 35XCB bullet).

I hear you AJ, I'll definitely be doing some experimenting with the 358009 with the nose unsized. So far the target holes haven't shown any tipping or key holing.

At this time getting the rifle to shoot ANY load with consistency is priority one; I need to rule out rifle problems. Shooter error will always be a problem to some degree:veryconfu

[oldblinddog]

The rear scope mount (Leupold style) had caught one of the lateral adjustment screws at an angle and was definitely not tightened down the correct way.

Bjorn, use these: Weaver Grand Slam bases and Leupold QRW rings. You won't have any more problems.

[rockrat]

Took my 358 Win. to the range yesterday. Was advised to try 3031, but only had some Benchmark which is a bit slower. Patterns with all boolits.
Went again today and tried 4895 and H-380. Patterns with 4895 and the XCB and about 3" groups with the NOE 235 RD mould and same with the 35-200. Had loaded up only6 rounds with H-380. Gun is a Remington xr100 that JES rebored with 5 groove rifling and chambered in 358Win.
Shot the H-380 loads first. First shot was way low left, but expected it to be away from the aiming point as I had some leading in the barrel. Figured to just shoot it out. Next 5 shots were just left of the aiming point. If I would have caught the wind switch from lightly at 3 oclock to 10-15mph or so, at 8 oclock, might have had a better group. Last shot was about 1/2" to the right of the group

Last 5 went into 1.5" with the first 4 around an inch. Load was r-p cases, fired 4 times, 45.6gr H-380 powder, sparked by a ww LRmag primer. Loaded to just touch the lands. Alloy was linotype with 0.2% Cu., sized to 0.360". Forgot my chrony

http://i34.photobucket.com/albums/d149/Bigdog337/35xcb%20001_zpsiccelccy.jpg (http://s34.photobucket.com/user/Bigdog337/media/35xcb%20001_zpsiccelccy.jpg.html)

[CJR]

Bjornb,

I have some comments on your 35XCB tight 100yd. groups and patterns at 200 yds. At first, I thought maybe the separation between CP and CG , on the 35 XCB bullet, was incorrect. So I did a quick check and the CP is where the drawing says it should be. Then I looked at how far the CG moves forward, when exposed to high presiure, and it did not place the CG in front of the CP. Therefore, I concluded the following:
1. The 35XCB taper + long ogive minimizes the effective bearing length.
2. Shorter bearing length CB can yaw/tilt excessively if shot with digressive powders (i.e. sharp spiked pressures which tilt/yaw the CB in the barrel)
3. Separation between CP & CG is only important AFTER the CB leaves the muzzle. The greater the CP-CG separation the stronger the gyroscopic restoring moment to pull an aerodynamically/wind yawed bullet back on the flight path so its axis is coincident with the flight trajectory. This instant gyroscopic correction keeps the CB on the flight path and promotes accuracy.

Here's what I suggest:
1. Use the hardest CB possible. This minimizes yaw/tilting of the CB while in the barrel.
2. Try a progressive powder, i.e W760. This starts the CB slower but gives a higher velocity than digressive powders. Digressive powders tend to tilt/yaw the CB before they start moving in the barrel.
3. Try another CB design with a long cylindrical shape and a short nose length. Something like the 311291 or Lee style CB. Seat them long to obtain more bore diameter engraving/guidance on the CB to minimize yawing/tilting while the CB is accelerating in the barrel.
4. Try hard to recover some fired 35XCB. If you have in-bore yawing/tilting, the engraved rifling marks on the recovered CB will clearly show that.

Bottom line- I suspect you have in-bore yawing/tilting. The yawed CB "cones" on muzzle exit, i.e. tip rotates in a circle and the base rotates in a circle as well. The rotating CB looks like an "hourglass". The CB flight spiral then increases in diameter as the range increases and patterns show up on targets at longer ranges.

Best regards,

CJR

[Bjornb]

Bjornb,

I have some comments on your 35XCB tight 100yd. groups and patterns at 200 yds. At first, I thought maybe the separation between CP and CG , on the 35 XCB bullet, was incorrect. So I did a quick check and the CP is where the drawing says it should be. Then I looked at how far the CG moves forward, when exposed to high presiure, and it did not place the CG in front of the CP. Therefore, I concluded the following:
1. The 35XCB taper + long ogive minimizes the effective bearing length.
2. Shorter bearing length CB can yaw/tilt excessively if shot with digressive powders (i.e. sharp spiked pressures which tilt/yaw the CB in the barrel)
3. Separation between CP & CG is only important AFTER the CB leaves the muzzle. The greater the CP-CG separation the stronger the gyroscopic restoring moment to pull an aerodynamically/wind yawed bullet back on the flight path so its axis is coincident with the flight trajectory. This instant gyroscopic correction keeps the CB on the flight path and promotes accuracy.

Here's what I suggest:
1. Use the hardest CB possible. This minimizes yaw/tilting of the CB while in the barrel.
2. Try a progressive powder, i.e W760. This starts the CB slower but gives a higher velocity than digressive powders. Digressive powders tend to tilt/yaw the CB before they start moving in the barrel.
3. Try another CB design with a long cylindrical shape and a short nose length. Something like the 311291 or Lee style CB. Seat them long to obtain more bore diameter engraving/guidance on the CB to minimize yawing/tilting while the CB is accelerating in the barrel.
4. Try hard to recover some fired 35XCB. If you have in-bore yawing/tilting, the engraved rifling marks on the recovered CB will clearly show that.

Bottom line- I suspect you have in-bore yawing/tilting. The yawed CB "cones" on muzzle exit, i.e. tip rotates in a circle and the base rotates in a circle as well. The rotating CB looks like an "hourglass". The CB flight spiral then increases in diameter as the range increases and patterns show up on targets at longer ranges.

Best regards,

CJR

CJR,
I don't disagree with much of what you're saying. The 35XCB has not been experimented with nearly as much as it needs to, and come winter I intend to rectify that. WW760 gave good velocity and acceptable accuracy in the 30XCB and could clearly stand a trial in the 35. As for bullets, there just aren't a lot of offerings in 35 caliber cast rifle bullets, and very few are "scaled up" from 30 cal.

Interesting about bullet hardness; the 30XCB shot best for me with linotype bullets, and I'm planning to cast up some NOE XCB bullets from lino and mono just to see what happens.

I tried to get in some shooting last Saturday, but only managed 2 series before the lightning alarm sounded and we had to clear the firing line. The rifle shot well, even though ES and SD with jacketed (Barnes X) wasn't very impressive. The full case load of AA4350 showed promise for accuracy even though it was found lacking in speed.
147615147616

[Larry Gibson]

No, I wasn't able to recover any bullets. What puzzled me the most was that I'd get tight groups at 100 yards but only spray-n-pray at 200.

Bjorn

Was this with the 35 XCB bullet or the 358009 bullet? My understanding from reading the thread it was the 358009 that fell apart at 200 yards as mentioned in post #34(?).

Larry Gibson

[Bjornb]

Correct Larry, it was the 2250 fps loads with the 358009 over IMR3031 that fell apart at 200. I have to drive over 2 hours to a 200-yard range, so I only got to test at the distance this once. At this point I don't want to rush any hunting loads for the 35XCB (since I have other rifles), and especially since I need to try shooting the -009 without sizing the nose.

So these 2 strings were just meant as more testing, trying to shoot the same loads in two different rifles to compare the accuracy. But weather cut me short and I'll finish up another day.

[runfiverun]

I just caught back up with this thread and need to apologize for the delay but work has kept me far from anything computer related.

CJR is giving some very good advice as to what could be happening here.
some time back Tim and myself had a discussion about mechanical and static fitment of a boolit.
and how the designs need to differ from each other.
if the collapse occurs in the mechanical stage and the design doesn't support that, it can lead to results like discussed above.
CJR gives the explanation on how the cog/cop relationship can give you fits when it flip flops mid throat so to speak.

[35 shooter]

Bjornb i was glad to see the 35xcb boolit come together for you a bit there. That's the best group i've seen from it so far. I've been shooting it in the whelen with 54 to 58 gr. of imr 4350 and 54 to 54 1/2 gr. usually shoots most any cast boolit well from this rifle. That's a bit over 2200 fps. depending on boolit weight...so right about where you are with the aa4350.

Think i'm getting too much contact in the throat when seating to the rifling in the whelen with this boolit. I'm going to back off a bit and give it a run at the rifling.

Since you did so well at about the same speed, i'm hoping that will be the charm. Oh well, i didn't name my rifle "ol contrary" for nothing.

Thanks for posting your results on it and that was good shooting!

[Bjornb]

Yeah like I said earlier, the 35XCB was never given the thorough workup that we gave the 30 cal. version. That will be changed once the weather cools down a little; my winter project is to get this cartridge to shoot well in both bench and hunting rifles.

Leaving for moose tomorrow (I shouldn't say that and jinx myself), and I decided to go with my Marlin 1895 GBL (completely gone through by Goodsteel, cycles like butter), loaded with the 350 RD GC bullet over RL7. As a backup rifle I'm bringing the Ruger Gunsite scout with jacketed ammo.

I'm getting the Mihec 359-220 hunting bullet in the GB that just closed; that will give me another design to try against both the NOE 360-200 FN, the 35 XCB and the 358009 (minus nose sizing).

Experimenting at the range is half the fun!

[taco650]

Yes indeed! Good luck on the hunt!

[OnHoPr]

May I ask what is the time frame of the 10 shot string, 5 , 10, or 20 minutes? Oh, was it fun hauling all that moose meat out?

[swheeler]

Yeah like I said earlier, the 35XCB was never given the thorough workup that we gave the 30 cal. version. That will be changed once the weather cools down a little; my winter project is to get this cartridge to shoot well in both bench and hunting rifles.

Leaving for moose tomorrow (I shouldn't say that and jinx myself), and I decided to go with my Marlin 1895 GBL (completely gone through by Goodsteel, cycles like butter), loaded with the 350 RD GC bullet over RL7. As a backup rifle I'm bringing the Ruger Gunsite scout with jacketed ammo.

I'm getting the Mihec 359-220 hunting bullet in the GB that just closed; that will give me another design to try against both the NOE 360-200 FN, the 35 XCB and the 358009 (minus nose sizing).

Experimenting at the range is half the fun!

So how did the moose hunt go? Pictures?

[Bjornb]

So how did the moose hunt go? Pictures?

No moose; only saw cows and calves. The 50-inch plus bulls got the memo and stayed away. We had visitors at the cabin:
150272150273150274

No open season on these, so we'll be trying again next year.

[swheeler]

It happens! Hope the stars align for you next year.

[taco650]

Bjornb,

Sorry to hear you had bad luck with the moose. Why didn't you get a caribou tag too?

[Bjornb]

Bjornb,

Sorry to hear you had bad luck with the moose. Why didn't you get a caribou tag too?

I had a caribou tag (and both brown and black bear tags), but this Game Management Unit would only allow for taking bulls. The visiting caribous were a cow with her calf.

[taco650]

I had a caribou tag (and both brown and black bear tags), but this Game Management Unit would only allow for taking bulls. The visiting caribous were a cow with her calf.

That's a bummer! Hope you enjoyed the trip anyway.

[kens]

Bump on this thread
Any more news on the 35XCB testing?

[Mauser 98K]

there is one little problem with wanting to go with a very slow twist with a long bullet, and this might explain why the groups is so large.. a slower twist imparts less gyroscopic forces upon the projectile leaving room for destabilization and degradation of accuracy, the same goes with slower velocities.. to remedy this one must either push the bullet harder in a slower twist barrel to get adequate stabilization or increase the twist rate to compensate for the slower velocities.. the longest bullet of that cal at 2250fps will usually stabilize with a 1-14 twist barrel is 1.5in long, at the 1,300fps the max length is 1.165in long in a 1-14 twist. longer bullets or slower bullets will not effectively stabilize enough to get the groups to 1MOA or less..

i went through this myself a while back when i started swaging and casting my own bullets.. the longer the bullet got the more unstable it got in the slower twist barrel and the slower the velocity the more unstable it got for a long bullet. this caused the group to open up or in extreme cases the bullet would start to tumble as soon as it left the barrel and it would keyhole and do other strange things.. to figure out if your bullet will stabilize in your barrel you must know the length of the bullet, the velocity you plan to use, and the twist and do some fancy math called the "Greenhill equation". or you can use this little calculator.. http://kwk.us/twist.html

this is the largest problem with a lot of people who think longer or heavier bullet is the way to go without really knowing what the laws of physics are or any knowledge of how rifles really work. the problem with this is that you can only push a long heavy bullet so fast b4 you grenade your rifle with the chamber pressures so one must either shorten the bullet for a given velocity and caliber or increase the twist rate to enable the bullet to stabilize enough for accurate flight at the slower velocities. there is a reason the old mauser with 0.323 bullets had a twist of 1-10 or faster, it was because the slower twist would not stabilize a long heavy projectile at any real range. the further the range the slower the bullet and it would start to wobble and yaw. this sounds like what is happening out at 200m as the bullet is now too slow to be stable with that slow a twist or length of bullet. barrel twist and gyroscopic stabilization and its effects on accuracy was figured out over a hundred years ago..

but for a lead bullet i would also not under any circumstances resize the bugger as long as it was within 0.003in. it is lead and the barrel resizes it. i use .310 bullets in my .308 target rifle at velocities down to 1,000fps and can get under 1MOA all day and im using the Lee dippers and not weighing a thing.. i have actually went as far as to put 15rounds in a hole i can cover with a nickle with lead round nose bullets at 50m. you must tailor the bullet as well as the other components to the rifle if you want to tighten the group up. shorten the bullet a bit and see if that is better if you can..

[Nrut]

The 35 XCB will easily stabilize in a 1/16" twist down as low as 1000 fps..

http://noebulletmolds.com/NV/images/N.O.E._Bullet_Moulds_360-228-FN_(GC)_Sketch.Jpg

Berger Twist Rate Calculator:
http://www.bergerbullets.com/twist-rate-calculator/

In the day when the 98 Mauser was a main battle rifle the jacketed bullets were new and of lower quality, read less balanced than today, hence the faster twist..
There was a thread sometime ago on 24hr. Campfire that discussed the twist rates of the old military rifles...

Cast bullets are more delicate than jacketed bullets and must be started straight and square with the bore or they become mangled, and out of balance..
Throat and bullet design, BHN and pressure along with pressure curve play a big role also..
A slower twist is more gentle on a cast bullet and is why it is prefered over a fast twist if goal is high velocity..

[GARD72977]

In intrested in this caliber. I dont care whats new or old when a case has a good ne k for cast bullets its intresting.

[Mauser 98K]

an unbalanced bullet will not stabilize no matter how fast you spin it. if anything it will wobble faster around its center of gravity and the groups will open up even further.. but if you want to get into the older bullets not being as good as today. a lot of the bullet manufacturing equipment that is being used these days is the old EW Bliss press systems or equivalent that were built over 50 years ago. it is the same equipment used way back then. in fact Mr Hornady started with one of the old surplus presses. as far as making bullets go not a lot has changed in the actual creation of the bullets. the materials might be a little different and the inspection process might have went computerized but the way they are made is virtually unchanged..

but back to the stability and twist... ya can do what you want in that department. there is no reason that a rifle cannot get sub MOA with cast bullets other than the thing is not stable or the loading is inconsistent..the other reasons would be shooter error, ammo is low quality, or the rifle has issues. but something has to be off with the stability if the groups cannot be brought to 1MOA or less and the groups keep going to **** at longer range. the only logical explanation from the observations is that the bullet is losing stability at longer ranges as the velocities drop and the bullet spin is less and that is what is causing the group to open up like it does. the way to rule out shooter error is to put the rifle in a cradle and set it up where it is mounted solid and do a group with it mounted solid, only then can you tell exactly what the rifle is doing..

another thing it could be. i see there is no cheek pad on that rifle.. accuracy will also suffer if you cannot get your head in the same location every time. this is why i got a raised section on my stock to rest my cheek on that ensures a exact cheek weld every time.. also is the barrel free floated or does the stock touch it anywhere. if there is varying pressures on the barrel that will cause problems also.. you want to be able to slide 2 playing cards all the way to the action for best results. this insures there is no chance of anything touching the barrel.

all i can do is put out the information, i cannot make anyone do it. and information is useless unless it is used..

[Larry Gibson]

Unbalanced bullets do in fact, stabilize.

Please, let us not confuse bullet stability with the decreases in accuracy unbalanced bullets can have. Unbalances in bullets is the primary reason why we shoot groups instead of all the bullets going into the same hole. The reason many old rifles shoot so much better these days is because the quality (read that; uniformity of jacket thickness and balance) of the commercial jacketed bullets is much better.

[Mauser 98K]

what causes the decrease in accuracy with an unbalance bullet then? while it is true the bullet will rotate along the center of gravity as soon as it leaves the barrel it does not necessarily mean that it is stable in flight as the gyroscopic forces will tend to want to yank the bullet one way or the other as the bullet wobbles around the center of gravity. a truly stable bullet will rotate along the center of gravity that is in the exact center of the axis of the rotating bullet. if it is rotating outside that exact center then it will not be stable enough for perfect accuracy.. there is a reason that unbalanced bullets result in accuracy problems, if it were stable then this would not be the case..

but we can demonstrate this effect by filing a notch or drilling a small hole in one side of a hand full of bullets to throw them off balance and then shooting that at the target.you can also swage the bullet core with a small plastic bead to one side of the core to create a void of lighter material that will also throw off the bullet. the more unbalanced you make the bullets the more erratic the grouping will become till you can no longer even hit the paper. and it does not matter how fast you spin or drive these bullets you can never get them to stabilize enough for a good group. but as i said, while it will stabilize around the center of gravity, while it wobbles around the center of gravity it will get a differentiation of the air pressures on different parts of the bullet and this will also create turbulence in places you would normally not have them and that also effects the trajectory. there is a whole slew of things that happen to a unbalanced bullet, not just rotational stabilization along the axis of the rotating mass.

the biggest reason for lead bullets to become unbalanced is due to air cavities in the lead, you might not be able to tell it by looking at the bullet but one side would be heavier than the other and these will cause fliers.. uniformity in the jacket thickness is only part of the equation with a jacketed bullet. if the base is at an angle or the core is not swaged in the jacket correctly there might be air trapped between the jacket and core and that will throw the bullet off and cause accuracy problems..

http://bisonballistics.com/articles/barrel-twist-and-bullet-stability

[Larry Gibson]

You've all the right parts there. Problem is your not understanding what bullet stabilization is. Bullet stability is simply that the bullet has enough rotational spin to fly point forward. Bullets can be very stable yet inaccurate.

It is the centrifugal force of the RPM acting on the imbalances that causes the inaccuracies. The higher the RPM the greater the inaccuracies.

[Mauser 98K]

yea, stable enough to fly point forward is a kind of stability.. and i agree that there is such a thing is too much spin.. they tried different twist with the .223 back in the day. one twist they had was so fast that the bullet was on the verge of flying apart and would detonate when it hit a blade of grass.. accuracy was out the window also.. as with everything there is a happy medium there where things work good... but that is what i would do though, id try a shorter bullet just to rule that out as a factor. what is there to lose? and b4 id go whittling off parts of the barrel id juggle the ammo weights and lengths a bit. always try the simpler stuff first because it is hard to add metal back after you machine it off or cut it off.. but if it was capable of 7 bullets in the same hole as outlined in the opening post then it is not the rifle and i can bet you it is the ammo.. if that is the only factor changed then it is something worth looking into.. id try to duplicate the load that did the good 7rnd group..

[Eldon]

This has been an interesting read. I am flummoxed as to what this cartridge will do that a 35 Whelen IMP will not?
(If the bbl is set up for heavy CBs.

I believe the 35W as the 400W has been misserved by having a non G&H chamber as the SAMMI standard. The G&H chamber (as researched by Mike Petrov) is less tapered and has a distinct shoulder. The 35 would have done better w/the same shape. The 35W IMP does the same albeit a bit different shoulder.

Picked up a nice FI FN that's going to become a 35W or 9.3x62. Choices ---- always choices !

[Eldon]

This has been an interesting read. I am flummoxed as to what this cartridge will do that a 35 Whelen IMP will not?
(If the bbl is set up for heavy CBs.

I believe the 35W as the 400W has been misserved by having a non G&H chamber as the SAMMI standard. The G&H chamber (as researched by Mike Petrov) is less tapered and has a distinct shoulder. The 35 would have done better w/the same shape. The 35W IMP does the same albeit a bit different shoulder.

Picked up a nice FI FN that's going to become a 35W or 9.3x62. Choices ---- always choices !

[Larry Gibson]

"This has been an interesting read. I am flummoxed as to what this cartridge will do that a 35 Whelen IMP will not?"

The 35 XCB (35x57) was designed to feed out of standard Mauser actions w/o any action modifications. The 35 Whelen IMP most often will not.

The 35 XCB (35x57) was designed to have a bit larger case capacity than a .358W with the longer neck of the Whelen. That case capacity for use with slower burning powders has been found optimum with cast bullets up through 250 gr giving excellent accuracy at HV. The 35 Whelen Std/IMP in a Mauser action often requires deep seating of the heavier bullets to fit magazine length.

The 35 XCB (35x57) was designed to use readily available shortened 35 Whelen dies for reloading. The 35 Whelen IMP requires expensive custom dies.

The 35x57 with the 35 XCB bullet will also fit in 3" Mauser magazines and in many "medium length" actions magazines. The 35 Whelen IMP will not.

As you said......"choices"......the 35 XCB (35x57) makes for a fine choice to the OP and others..........