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garandsrus
11-12-2007, 02:40 PM
Hi,

I just wanted to share a target with 6 keyholed boolits. It would be hard to reproduce such a perfect set of profiles! :drinks:

http://i106.photobucket.com/albums/m245/johntlarson/tumbling.jpg

The same boolit groups < 2" at 50 yds in the same rifle, so it's not a rifle, boolit, lube, or alloy problem. I changed a few things so I need to figure out which one is the culprit. Here are the specifics for the rounds that tumbled:
Rifle - H&R 38-55 Target Rifle
Boolit - Lyman 375449, gas checked
Alloy - WW
Size - .379
Lube - Bullshops Speed Green
Brass - Starline 38-55
Powder - 20gr and 21gr 2400

The thing that I changed from the "good" load was the brass and seating die.

The brass I used in the past was blown out 30-30 and .375 Win. The loading dies were .375 Win. The boolit was seated to where it lightly engraves. This leaves the last lube groove (without lube) seated out of the case. The groups are about 3-4" at 100 yds. with the issue sights.

The new batch of boolits that keyholed were loaded with Starline 2.125" 38-55 brass and a set of RCBS Cowboy dies. These were new cases and were not resized. Only the seater die was used. A light crimp was used. I loaded the rounds on a Dillon 550B so the expander die wasn't used. The powder funnel expanded the case enough to start the boolit without shaving any lead.

The overall length of the two loads was almost identical. It will be interesting to figure out what caused the difference in performance.

Any thoughts on what the cause will be?

John

Bass Ackward
11-12-2007, 03:23 PM
Any thoughts on what the cause will be? John


John,

No offense, but that group looks like a typical driving pattern for my wife in the winter. Scared hell out of me for a second.

Ricochet
11-12-2007, 03:25 PM
You're getting excellent consistency with that load!

Larry Gibson
11-12-2007, 03:30 PM
That's an accurate load....ya got one 10X!

Seriously, something really went wrong there, will have to ponder on that for awhile.

Larry Gibson

garandsrus
11-12-2007, 03:39 PM
Larry,

That shot in the middle is really beautiful....

I may have to crop the others out of the picture, which isn't hard since they are not in the 9 ring or better and use it as a new wallpaper or something :)

I forgot to mention that the target is from 50 yds. I couldn't hit it from 100...

John

Tom Myers
11-12-2007, 04:24 PM
Check the length of the brass that was giving fair results against the Starline 2.125" brass. Then either make a chamber cast or a pound cast of the chamber to determine the correct length for the brass.

It is quite probable that the rifle is chambered for the new, short 38-55 brass and not the old style 2.125" brass.

Tom Myers
Precision Ballistics and Records (http://www.tmtpages.com)

grumpy one
11-12-2007, 04:55 PM
This may be way out, but was there by any chance a larger seating force required than with your previous more successful loads? If so, perhaps your new brass either has a thicker or a harder neck, or your new sizing die is a bit undersized, and you have swaged down the bullets when forcing them into the cases. I suggest this on the basis of two prior experiences. First, if I shoot factory loads from the grossly oversize barrel in my 336 30-30 I get targets that look exactly like yours. If I use either properly sized cast bullets or 0.311 J-bullets I get decent groups with no slightest sign of bullet tipping. This suggests that your bullets may be ending up undersized. The second prior experience is that I find if I use new Winchester brass in my 30-06 it lasts well, but if I use new R-P brass I need to anneal it before first use or the necks crack after 5 loadings or so. Annealing the brass makes bullet insertion way easier and I end up with much less neck tension.

I'm not suggesting that I've found your solution here, but it does look to me like a possibility you could consider - especially if you are finding bullet insertion force higher with your new brass and different sizing die. My suggestion has much the same outcome as Tom's - if your brass is overlength the bullet will be getting swaged down as it emerges from the case.

686
11-12-2007, 05:06 PM
unless you turned the target you are hi and to the right. would make good holes in a deer. maybe they would be stright at 150 yrds.

Blammer
11-12-2007, 06:26 PM
what primer? did you go to a normal from a magnum or vice versa?

I'd also check your case volume, may have gone to a larger case that would reduce pressure and velocity.

Looks like your boolits need some more speed.

Old Ironsights
11-12-2007, 06:33 PM
That target's a keeper...

Dale53
11-12-2007, 07:55 PM
Now, THOSE are Keyholes! So often you see someone call a "tipping bullet" a keyhole. THESE are keyholes.

I agree with the consensus. It appears to me that we are dealing with something that reduced the size of the bullets.
Keep us posted.
Dale53

Misfire99
11-12-2007, 09:06 PM
One of the ways you can get the OAL for a chamber is to drop a rod down the bore with no round in place. Mark the rod,I use a file. The drop the bullet you want to use into the chamber and hold it in place with something. A dowel of even a sized brass will work. Then drop the rod in again, but don't unseat the bullet. Then mark the rod again. The distance between the marks is the max OAL. You can use this as a starting point when setting the OAL for your rounds.

45 2.1
11-12-2007, 09:12 PM
Any thoughts on what the cause will be? John

That's an easy one. The cause is the dead soft annealed cases. Try work hardening some of the new cases by sizing and expanding without belling several times and retest. Several of us have ran into the same problem with higher intensity straight walled cartridges.

mooman76
11-12-2007, 09:19 PM
Looks like you were using the ladder method!:kidding:

Scrounger
11-12-2007, 09:26 PM
Now, THOSE are Keyholes! So often you see someone call a "tipping bullet" a keyhole. THESE are keyholes.

I agree with the consensus. It appears to me that we are dealing with something that reduced the size of the bullets.
Keep us posted.
Dale53


Like the Lee Factory Crimp Die?

Pat I.
11-12-2007, 09:46 PM
I'm going with the brass being too long. Chamber a resized case minus the bullet and see if it looks like it had a trip through a crimp die.

Onlymenotu
11-12-2007, 10:22 PM
:roll: jeesh what's the problem instead of 3/8's holes...... your get'n perfect 3/8's x 1" holes * makes for a bigger blood trail* :drinks: now all ya gota do is tight'n the group up to the 9x and 10x rings and your all set [smilie=1::Fire::Fire:

garandsrus
11-13-2007, 12:37 AM
Thanks for all the ribbing... I mean help :)

Here are a couple responses to the ideas presented, in order of the post it was submitted in:

Tom Myers - It is quite probable that the rifle is chambered for the new, short 38-55 brass and not the old style 2.125" brass.

Several other folks had reported using this same brass in the rifle with very good results which is why I bought it. I had been happy with the blown out 30-30 and .375 cases. Before I loaded any rounds, I took a new case and tried it in the rifle. It slid right in and the action locked up with no hesitation. I measured the OD of the case neck before chambering and then closed the chamber on it 5 times. The neck measurement didn't change. The loaded cases chambered without any hesitation also so the brass isn't getting hung up. I do have some cerrosafe so I can make a chamber cast. I have never done one before.

Grumpy One - If so, perhaps your new brass either has a thicker or a harder neck, or your new sizing die is a bit undersized, and you have swaged down the bullets when forcing them into the cases.

This is what I though would be the culprit so I saved one loaded round. Maybe I was just chicken, I didn't want to ruin my target! I pulled the boolit with a kinetic puller and pulled one that was loaded in a blown out 30-30 case. The result is that neither boolit was sized down when loaded and they both measure the same. The Starline brass actually has thinner necks than other brass which is why people suggested it for the H&R which sometimes(?) has larger bores than throats. I don't think I have the chamber/throat mismatch since I was able to chamber .379 boolits when other people were not.

686 - The target is rotated in the photo. The bullets were impacting a little low and quite a bit right.

Blammer - No primer change... I did check the primers for pressure signs after your comment. I hadn't noticed anything unusual at the range. The 38-55 primers are a little flattened and showing higher pressure signs than any of the re-formed 30-30 cases I looked at. I knew that 20 to 21 gr 2400 was near a top end load.

54 2.1 - That's an easy one. The cause is the dead soft annealed cases. Try work hardening some of the new cases by sizing and expanding without belling several times and retest. Several of us have ran into the same problem with higher intensity straight walled cartridges.

I understand what you wrote, and understand that neck tension could be less on these rounds, but don't understand why this would cause tumbling. Can you elaborate? The only thing I can think of is that the reduced case tension might release the boolit too easily, causing the powder to not burn with enough intensity, resulting in low velocity. I didn't chronograph these rounds but the recoil was about what was expected. I will chronograph them next time. I have had good accuracy with 8gr Unique, which I also didn't chronograph. I did chrono 9.5 gr Unique in the blown out brass and it gave me 1200fps so 8.0gr would probably be just over 1000fps with OK accuracy. I also chrono'd 20gr 2400 with the old brass and it came in at 1670fps. I was looking for a higher velocity load (1500-1600 fps) as I am running out of rear sight elevation at only 100 yds.

Scrounger - I didn't use the factory crimp die on the 38-55 brass. I used the seating die to lightly crimp the round. I did use the FCD on the 375 Win loading dies. The crimp is light.

Pat I - Chamber a resized case minus the bullet and see if it looks like it had a trip through a crimp die.

I haven't chambered a resized case yet. I didn't get any change in measurement at the case mouth when a new case was chambered multiple times. I re-chambered a fired case 5 times also and there wasn't any difference in the case mouth diameter either. The case wall appears to be straight. I checked a new case and the mouth OD was .386. A fired case is .392. The case wall is .014-.015 thick, measured with a standard caliper.

Onlymenotu - I did see a lot of confetti from the target after each shot!

I now have some once fired brass to test 45 2.1's solution.

There is no visible leading in the barrel... I put a couple patches through it and all I got was powder fouling.

Thanks again for all the ideas...
John

45 2.1
11-13-2007, 07:41 AM
I understand what you wrote, and understand that neck tension could be less on these rounds, but don't understand why this would cause tumbling. Can you elaborate? Annealed case necks can produce very poor accuracy out of some straight walled (or some BN cartridges for that matter) cartridges, why we don't really understand fully. Probably from no guidance or reduction of ignition pressure, but we know it happens and don't fully anneal anything because of it. The only thing I can think of is that the reduced case tension might release the boolit too easily, causing the powder to not burn with enough intensity, resulting in low velocity. I didn't chronograph these rounds but the recoil was about what was expected. I will chronograph them next time. I have had good accuracy with 8gr Unique, which I also didn't chronograph. I did chrono 9.5 gr Unique in the blown out brass and it gave me 1200fps so 8.0gr would probably be just over 1000fps with OK accuracy. I also chrono'd 20gr 2400 with the old brass and it came in at 1670fps. I was looking for a higher velocity load (1500-1600 fps) as I am running out of rear sight elevation at only 100 yds.

Wayne Smith
11-13-2007, 12:45 PM
Since Those Who Know More Than I haven't mentioned this, I may be wrong. It strikes me that your crimp was vastly different between the two, one with a "light crimp" from seating die, the other with the Lee Factory Crimp Die. Combined with the evidence of higher pressure in the Starline cases, i.e. primer flattening, could we not be looking at significantly faster velocity? Would this be enough to cause keyholes? I have no idea, but thought it should be mentioned.

leftiye
11-13-2007, 05:53 PM
Wayne, Only if the bullets were over spun which would probably only unstabiize them somewhat, or if the added velocity caused major damage to the boolit or drastic leading would keyholes result. There are several threads going on here right now that suggest that the"damage" from oversized overhard boolits, and /or H&R type non throated chambers with no leade can cause keyholing though.

MGySgt
11-13-2007, 08:35 PM
This is one time that I have to disagree with 45 2.1. With the blown out WW and Rem brass the case necks were thin and you would get a good seal.

Check the sides of the star line brass and I think you will find them blackened from not sealing the chamber with these relitively low pressure loads.

This can also be compounded by a loose neck fit and a lighter crimp - you are not getting enough velocity to stablize the bullets.

I have a similar problem with my 45/90 and star line brass being thicker and stronger then the old Black Powder brass.

New Star Line brass without annealing for a 19,000 PSI load = 5 to 8 inch groups at 100.
Annealed Star Line Brass goes between 1 and 1.5 inch consistantly.

Just my .02 worth - that and a buck will get you a cup of coffee.

Drew

1Shirt
11-13-2007, 08:47 PM
For what ever it is worth, the last time I saw keyholes like that was from a 6.5x55 Swed Carbine, that had the crown buggered up. When it was recrowned, it shot the same loads on point. Probably not applicable here, but felt it ought to be added.
1Shirt!:coffee:

John Boy
11-13-2007, 10:24 PM
John, my first guess is you are pushing the 264gr bullet to fast using 20-21gr of 2400. Back it down to 15-17grs. That will get you in the 1500 fps range. Also, mic the base of the bullet. If it is in the 375 range, it's too small. Here are the barrel specs:
• Factory spec ... Bore – 0.373 and 0.379 grooves
• Actual: 0.374 bore and 0.378 groove
So, you'll need a 380 bullet base in the H&R.

Then, the next issue jumps out. Their chambers are based on a Winchester factory load.... too small! The chamber needs to be reamed out to 398-401 so the loaded 380 round will fit in the chamber

Give this article a read ... http://www.brimstonepistoleros.com/gazette/jan06.html

and then send an email to Old Scout (40+ years of gunsmithing and a 38-55 crank) who has the reamer
R. F. Clark, Gunsmith
640 Emerald St.,
Upland, Calif. 91786
909-984-1548
Old Scout (o.scout@verizon.net )
He charged me $25 plus shipping

I have no idea of the fps using the 20-21gr of 2400, but has to be way over 2000 fps. The H&R only has 002 groove diameter, so at that speed the bullet is not obturating and when it hits the muzzle - flippity - flop all the way to the 50 yd target and into the wild blue yonder at 50+ BTW, save that target, it's a classic [smilie=1:

I'm using 21gr of 5744 for the 335gr Snover with excellent success out to 300yds. 2400 and 5744 are is the same burn rate area. If you want to shoot Black, the Snover and 42grs of FFg

As for the new Starline 2.125's in the H&R ... I have no issues with the extra case length

garandsrus
11-14-2007, 01:22 AM
Thanks for the additional responses...

1Shirt - The crown is always a good thing to check! The rifle is new and has a recessed target crown with no damage.

MGySgt - the cases look as clean as they did before firing. These are not low pressure loads!

John Boy - My boolits are sized .379 and are gas checked. I don't have any trouble chambering the rounds. I would like to try .380 and .381, but I don't have a sizer in that size yet. I have one of the group buy molds that Buckshot ran that will cast a boolit 383+.

I did chronograph some loads using 2400 (previous range trip) using the blown out 30-30 brass in this rifle. Here are the results:
Gr Velocity
16 1415
17 1469
18 1527
18.5 1532
19 1607
19.5 1624
20 1672

The load that produced the best groups was 18 to 18.5gr.

I also tried a number of loads of IMR-4895 and while they shot fine, all loads left unburnt/burnt powder in the bore.

Thanks for the article link...

John

Pilgrim
11-14-2007, 01:22 PM
I guess I'm out of it as I'm not sure I understand the confusion. Two things jump out at me. You indicated that the target displayed had been turned and the loads were actually low and right. LOW is the word that jumped out at me. The second thing that falls in my mind is that any boolit (and/or bullet) has to be driven fast enough in whatever twist rifle you have to stabilize it. That is, spin it fast enough to stabilize. Since your bullets are low, and key-holing, the velocity is probably lower than the previous successful load. A second possibility is the velocity is quite a bit higher than the previous load. The same thing happens with handguns. Higher velocity often strickes lower on the target due to less recoil time. I'd look at one of two issues. 1) For whatever reason, the pressure of your load is low and producing low velocity. OR the pressure is quite a bit higher and velocity is higher. Your next range session with a chronograph should answer that qustion PDQ and will allow a comparison between the previous successful load and the current key-hole abomination. 2) If the velocity is high, then the boolit is either too soft which is allowing it to skid rather than engrave, OR it is too hard which is not allowing it to fully engrave. If the velocity is low, then you aren't getting enough pressure early in the ignition (crimp is too light) and the 2400 isn't buring properly. That's the best I can do this early in the morning. FWIW...Pilgrim

garandsrus
11-14-2007, 04:36 PM
Pilgrim,

Thanks for the response... Yes, the shots are low and right. I don't know if that means anything though with a tumbling boolit.

I will be out deer hunting for a few days so test results with a chronograph will need to wait a week or so.

The tests will consist of new 38-55 brass, once fired 38-55 brass, blown out 30-30 brass, and new 38-55 brass that has been sized/expanded 5 times prior to loading. I will use two powder charges, 18 and 20 gr 2400.

John

Pilgrim
11-14-2007, 05:06 PM
You might be wasting components. There is something distinctly different between your blown out 30-30/375 brass and the new brass, or you wouldn't be seeing the tumbling. I'd simply load your standard load based upon the .30-30 brass and some with the new brass. All other things should be the same as you have indicated. If BOTH of the loads are tumbling, then I'd look at the different die sets. In fact, I'd be tempted to load one set with each of the die sets you have used. Make the first shots with your old routine, next shots with the new reloading routine (tools, etc), and repeat with the new brass. Make sure you put all of them over the chronograph. The targets and chronograph will tell you where to go next. It isn't the rifle, or the bullet as cast and previously sized, or you wouldn't have gotten good groups before. The rifle, mould, sizer, and lube didn't simply "go south" without something else getting in the middle of it all. Pilgrim

Bass Ackward
11-14-2007, 05:44 PM
The new batch of boolits that keyholed were loaded with Starline 2.125" 38-55 brass and a set of RCBS Cowboy dies.

The overall length of the two loads was almost identical. It will be interesting to figure out what caused the difference in performance.

Any thoughts on what the cause will be?

John



Since I haven't voted, I select these two statements. Key words from above are "new batch of bullets" and OAL almost identical and a set of "Cowboy dies".

Them babies are not tumbling or some holes would just show tipping. So the tipping occurred in the throat first in my mind and the strike on the target gives a hint of how early the bullet destabilized and turnt sideways losing more or less velocity. They actually stabilized, but in a sideways fashion.

Now was it too long of brass or cowboy dies? Most cowboy dies are made for cast with a very generous seater area to accommodate larger diameter bullets. Without the correct seater for a smaller diameter bullet, you are going to get run out the ...... well you know the anatomical part here. Run out is misalignment or manufactured tipping exaggerated by the change in OAL. I vote the dies.

If you hit a deer with them sidewinders, it ought to turn him inside out.

garandsrus
12-10-2007, 09:25 PM
I finally made it back out to the range... Here are the results:

All loads used the same batch of boolits, lubed the same, and gas checked the same, with the same primer and powder charge, and all went across the chronograph. All 30-30 loads were loaded with a set of Lee 375 Win dies. The 38-55 brass was loaded with a set of RCBS Cowboy dies in 38-55.

Load data: CCI LR Magnum primer, 20.0 gr 2400, Lyman 275449 ACWW, Hornady gas check.

Here's what the rounds look like. The short case is the 30-30 and the long case is the 2.125 38-55:
http://i106.photobucket.com/albums/m245/johntlarson/100_1558.jpg

Group one: 30-30 cases blown out. I shot 5 rounds to start the session and 5 rounds to end it. It's not the greatest group in the world, but all boolits went through nose first. Average velocity = 1642:
http://i106.photobucket.com/albums/m245/johntlarson/3030bras.jpg

Group two: New 38-55 brass. This pretty well replicated the first target with 3 of 5 shot keyholing. Two shots were great! Average velocity = 1580
http://i106.photobucket.com/albums/m245/johntlarson/newbrass.jpg

Group three: Once fired 38-55 brass. 4 of 5 were unstable. Average velocity = 1616
http://i106.photobucket.com/albums/m245/johntlarson/1xfired.jpg

Group four: 5x re-sized (but not fired) 38-55. Two shots missed the paper. Average velocity = 1619
http://i106.photobucket.com/albums/m245/johntlarson/sized5x.jpg

Pretty amazing... I guess my next step will be to load the 38-55 brass with the .375 Win dies to see if things improve. I have not measured the run out with either load, but I will try to do that. The 38-55 rounds are going about 20fps slower than the 30-30 rounds. It wouldn't think that's the problem. I have shot the 30-30 rounds at 100 yds with no problems. I would think they would lose significantly more than 20fps between 50 and 100 yds.

Any other suggestions?

Thanks,
John

Castinoff
12-10-2007, 10:04 PM
I tend to agree with Bammer on this one. Seems I've read a post here where someone was asking for opinions of Starline brass. Everyone agreed it was a great product but one also mentioned that Starline frequently has less case volume than other brands and to reduce starting loads and watch for pressure signs.

Ricochet
12-10-2007, 10:40 PM
Any way the mouths of those longer cases could be getting into the forcing cone of the chamber throat, not opening fully, and squeezing down the boolit bodies to a smaller diameter?

MakeMineA10mm
12-10-2007, 11:01 PM
Well, I'm not going to speculate, because I haven't key-holed many bullets in my life, and the ones I did were factory loads and it was the crown that was bad...

BUT, one thing I would caution you on: If you don't want to waste components, you need to only change ONE variable at a time. Start off with your old load in your old cases, with your old dies. That establishes a baseline.

Then, change to the new brass, but keep everything else the same: dies, bullets, powder, primer. If you get key-holes, you know it's the brass. Then, you just have to figure out why.

Then, switch back to your old brass, but change to the new Cowboy dies. Again, if you get keyholes, it's the dies. Probably something not machined correctly in them, and RCBS should take care of that for ya.

If neither of those things give you the problem, try different seating depths. I've heard of wrong seating depths hurting accuracy, but never key-holing, but I suppose anything's possible... Again, use your old brass, dies, etc., in other words everything that you KNOW works, just change the seating depth.

Don't change any of the powder, primers, bullets. Keep them the same. Only change one variable at a time, and that will isolate which thing it is. You ALMOST did that with your post from earlier today, but then I saw that you changed two variables at a time... That prevents us from knowing what is really causing this...

When you get the single variable that causes this isolated, then, these guys can give you ideas what to look for on that one thing.

S.R.Custom
12-10-2007, 11:21 PM
Now you know why they call it "tumble lube." :mrgreen:



But seriously...


Any way the mouths of those longer cases could be getting into the forcing cone of the chamber throat, not opening fully, and squeezing down the boolit bodies to a smaller diameter?

Of all the speculation here, this makes the most sense to me. Given sufficient velocity and appropriate bullet length/twist ratio, the only reason a bullet tumbles is insufficient contact with rifling. If the cases were a bit too long, the crimp would not be able to unroll, and you'd get some serious bullet swaging. I'd take a few of those problem cases, trim some down to the length of the others, and try them.

Or if the wife doesn't mind, squib load one of the problem cases with 2 grains of bullseye, go down into the basement, and put a round into a box of rags. Measure the slug...

A chamber cast would really be handy here.

nemo
12-10-2007, 11:27 PM
I have same Rifle With a .374 bore .376 grove and a tite chamber . I use .375 s And trim .125 off cases .After all that could you have a soft boolet or too hard .

garandsrus
12-10-2007, 11:33 PM
Thanks for the thougts...

Castinoff - The velocity change between the two sets of brass is only 20fps out of about 1600, which is only 1.25% difference, so it's pretty close!

Ricochet - I don't think so, but you never know... I will check a fired case to see if it looks like a problem with the rim but I didn't notice anything. The rounds chamber freely. I haven't made a chamber cast though. I have cerrosafe so I can make one. I could also trim .010 or so off a case as an easy check. I would think that the pressure and velocity would increase quite a bit also if that were happening, which the chronograph doesn't show.

10MM - The only reason I changed both the brass and sizer at the same time is that they are somewhat of a "matched set". The 38-55 dies should work with 38-55 length brass, and the .375 Win dies should work with .375 Win brass (which is equivalent to the blown out 30-30's). As I stated, my next step will be to load the 38-55 brass with the .375 Win dies and the .375 brass with the 38-55 dies.

Nemo - My rifle is pretty new and has the new "revised" chamber, so chambering .379 boolits doesn't present a problem at all. From what I understand, H&R is now cutting a more "correct" chamber than before. There is a certain serial number prefix that tells you which chamber it has. Why did you shorten your brass? The 30-30 blown out round with a long boolit chambers fine in my Win .375 BB.

Supermag - Great idea. I can do that tomorrow when the house is empty other than the dog! She won't tell...

John

georgeld
12-11-2007, 12:06 AM
John:

IT's enough to make you bald huh?

Have you slugged the bore?? Might be worth doing to make sure the dia. is correct even though they shot fine with the reformed brass. Just more info in the notebook mostly for reference.

I have a K 38, shoot the SWC @ 147gr pretty hard, 3.5gr Red Dot and shoot just fine.

Load the same thing in .357 brass and they keyhole. Why?? More space? Longer case?
Damned if I know, so I just stick with .38 brass and live with it.

Many yrs ago I tried cast in a 1917 Enfield '06 with near factory vel's. Not only had keyhole's, but, spatter holes too from molten lead, and or torn off chunks, plus the gas check came off most of them as it printed also. I gave it up and never messed with cast in rifle's since. That's about all I shoot in handguns now though. By the buckets full and the only problem I've had was with the .357 case keyhole's.

Be interested in learning the cure, so please don't drop it til you let us know.

Very interesting to read as these ideas.

Good luck,
George

shotstring
12-11-2007, 02:09 AM
The only instances of keyholing that I have personally experienced during 20 years of shooting were caused by bore being larger than the boolit, or by an unbalanced boolit, caused by damage during the reloading stage or cartridge feeding stage, or weight discrepency in the booit itself during its creation.

Hobie
12-11-2007, 09:20 AM
I one day (and not all day) had this happen with H4227 and the Lyman 375249. Does the H&R have the long chamber? Also, IME, 2400 really doesn't do well with a "light" crimp. A good firm crimp with good neck tension. Incomplete burn, but apparently consistently so, could do this when the necessary velocity isn't attained. Does raise the question of how they bullets were on target though... As I said, I had this happen one day in my .38-55 and I haven't figured it out yet. Never had a problem with the load before or since!

Bass Ackward
12-11-2007, 10:34 AM
Any way the mouths of those longer cases could be getting into the forcing cone of the chamber throat, not opening fully, and squeezing down the boolit bodies to a smaller diameter?


I am anxious to see this followed up. While I admit it could be the cases, I would think that something doing that much damage to the bullet, under a firing condition, would throw more pressure than to just produce a 20 fps velocity difference. Could be, could be.

Sorta like what's behind door number 3? The anticipation builds.

1Shirt
12-11-2007, 11:17 AM
In addition to all the rest of the thoughts on this subject, you might also want to have the muzzle crown checked.
1Shirt!:coffee:

Wayne Smith
12-11-2007, 02:50 PM
10MM - The only reason I changed both the brass and sizer at the same time is that they are somewhat of a "matched set". The 38-55 dies should work with 38-55 length brass, and the .375 Win dies should work with .375 Win brass (which is equivalent to the blown out 30-30's). As I stated, my next step will be to load the 38-55 brass with the .375 Win dies and the .375 brass with the 38-55 dies.
John

John, you are still changing two things at once. You can't isolate a single cause in this manner, just as 10MM said. "Should" doesn't make it, you need to know what's going on in this particular set of dies with this particular set of brass. The only way to do so is to change only one thing and shoot, then change another, on and on.

Ricochet
12-11-2007, 03:58 PM
Many yrs ago I tried cast in a 1917 Enfield '06 with near factory vel's. Not only had keyhole's, but, spatter holes too from molten lead, and or torn off chunks, plus the gas check came off most of them as it printed also.
I tried that a few years ago in a Mosin-Nagant M91/30 with plain base microbanded boolits tumble lubed with LLA over a charge of IMR 7383 that ran 'em through the Chrony at about 2100 FPS as I recall. Never did get any of those on the paper, so I don't know if they were sideways or not. Got some little holes in the plastic screen that I thought were due to the unburned powder that spits out with loads like that. But the bayonet was coated with rough chunky stuff that turned out to be lead, soldered firmly to the bayonet and very hard to remove. The bore was unleaded. Only time I've ever known I had lead melting off of boolits. Funny thing, when I switched the lube on those boolits to White Lightning bicycle chain lube, it stopped the molten lead splattering (or at least, kept it from soldering to the bayonet), but I still never got one to hit paper at 50 yards.

Shooting gas checked boolits at the same speed with the same powder, alloy and lube is no problem, and it's capable of some fairly decent accuracy.

As for raised pressures with swaging, I don't think swaging a lead boolit down enough to cause problems with rifling stripping would raise pressures that much. Think of the force you exert slugging a barrel. It's comparable.

charger 1
12-11-2007, 04:04 PM
I'll ask the same thing here I ask anytime I'm showed a target....Can you do it again?

405
12-11-2007, 06:36 PM
Yikes! Agreed, there is something going on. First I'd check the chamber length. Then the load itself. I have two original Win 94s in 38-55. They have been buggers to develop cast bullet loads for..... small chambers, big bores :( When I first started load testing for these guns I too had targets showing varying degrees of yawing keyholes!
But, during the very long process, I discovered (price of education) that there is an ideal balance among the following: diameter of bullet as it relates to chamber and bore/groove, BHN of bullet (obturation), weight/length of bullet (stabilization), type and amount of powder...again obturation and stability as it relates to velocity- there seems to be a threshold of velocity required to stabilize a bullet that is minimally stabilzed by a minimal bore twist rate. Just throwing a guess out here..... but at least one previous sage poster thought that the load (pressure and velocity) was not, for whatever reason, performing up to the previous acceptable load and I tend to agree. You may need to work on getting the pressure and velocity up a little by tuning the sizing, crimping, powder type and charge, etc. Those keyholes may be due to just a smidgen too little pressure or velocity to push the bullet past the RPM threshold required to stabilize. Related to that- if the pressure is a tad too little the bullet may not be fully obturating and not taking the full rifling as it should. The previous acceptable load that did stabilize the bullets may have just barely done so. Of course the opposite could be true where the new load is pushing the bullet too fast and it is "stripping" and not getting to full RPM?? But, I would think the former to be more likely. Anyway good luck! Been there, done that with two different 38-55s :mrgreen: sorry for the windy post

nemo
12-11-2007, 06:42 PM
Reason for shorten case is bullets were .379 caused case neck to stick in chamber hard to extract needed to pry out loaded. Pressure would have went up..378/9 too big. Thanks on info on chamber info, mine is where I want it, use smokeless and black subs . nemo

oneokie
12-11-2007, 08:18 PM
This is in no particular order;

You have never said how hard or soft the boolits are.

Also not stated is your groove size.

Only big difference I can see is the difference in crimps. One is FCD, other is a "light" roll crimp.

garandsrus wrote;

A fired case is .392. The case wall is .014-.015 thick, measured with a standard caliper.

This seems to be a very thick neck wall. With your stated measurements, a round loaded with a .379" boolit should be in the .420" range when it should be about .402".
Have you measured the neck dia. of a round loaded with the .379" boolit?

grandsrus wrote;

I would like to try .380 and .381, but I don't have a sizer in that size yet. I have one of the group buy molds that Buckshot ran that will cast a boolit 383+.

Have you tried any loads with "as cast" to see if they will chamber?

My .02 worth:

Load some test loads with the 375 dies using both kinds of brass. Use the FCD on the 30-30 brass, use the 375 seat die on the Starline brass, you will have to tinker with the crimp adjustment. Or you could use some shim stock under the FCD to get it to apply the crimp in the same relative location on the case mouth on the Starline brass. Try and have the same vertical dimension to the crimp on both makes of brass.

Do the same with the RCBS Cowboy dies.

My WAG is that somehow the difference in crimps is causing a change in the pressure curve.

405
12-11-2007, 11:44 PM
oneokie, Your points are well taken!

Looking at the data garandsrus posted I see a few possible problems.

garandsrus I'm going to stick my neck out here so don't jump too hard- just some things to consider :coffee:

If it were me trying to load that rifle with cast bullets to shoot accurately I would:

1) determine the chamber dimensions & trim brass to correct length if too long
2) slug the bore to determine bore and groove diameter- use bullet sized to
between groove diameter and about .001" over groove diameter- if compatible
with chamber neck dimension.
3) determine the twist rate of the bore (should be either 18" or 20" twist)
4) use only the correct type brass- Lyman has a very stern warning about
using 375 Win brass in 38-55s. Starline should be fine as would WW or
Jamison
5) consult several load manuals about possible loads- the 20 +/- grs of 2400
under the 265 gr bullet seems very hot/fast particularly if alloy is straight
wheelweight at about 9 BHN. If treated WW then hotter loads maybe OK.
6) try such powders as 5744 or Rel # 7 at lower end of recommendations.
7) try both crimped and uncrimped loads- if crimped, then make sure the cases
are all the same length and only lightly crimp with the seater roll..... also might
try the Lee FCD

Keep us posted- the more feedback info the better. This cast bullet stuff is so complex it resemblies an art form as much as a science!

leftiye
12-12-2007, 12:58 AM
In my Handi I use uncrimped and unsized loads. Size the neck if necessary enough to be finger tight (ie. you can even take the crimps out of the equation, but you must use powder that doesn't need a crimp to burn consistently.). Find out what your chamber necks measure, and if your chamber is long enough for the Starline brass (cast the chamber). Make sure neither of these is sizing your boolits down, and that the loaded ctgs. aren't "pinching" in the chamber (have enough clearance to release the boolit). Make sure your boolits are about groove diameter plus .001". Checkup on them NEF guys, and make sure your rifling is deep enough to work (slug the bore). This will let you know what groove diameter is too. Calculate the velocity necessary to stabilize the boolits with your twist (check the twist), and make sure your loads are at least that fast. Enjoy?

oneokie
12-12-2007, 11:55 AM
.02 more;

Your original post states that the Starline brass is new, unfired. You are not using the expander die with the RCBS Cowboy dies, you are belling the cases with the powder die on your Dillon. Neck tension would be unknown.

You do not say anything about sizing and expanding the 30-30 brass.

The expander for the Cowboy dies is .377".

Took a second look at the pic of your loaded rounds. The one on the right, Starline brass, appears to have an uneven crimp. More crimp on the left than the right.

Until you equalize all factors in your load work-up, there are too many variables to deal with.

My suggestions;

Load some of the once fired Starline brass, partially sized only to acheive consistant neck tension. Make sure the case mouths are square. Use the expander die to expand and bell the case.

The new unfired cases could have less internal volume, thereby increasing pressure, and possibly causing the boolits to strip the rifling.

My only experience with keyholes in target with 38-55 was due to stripping of the rifling. This was with a load listed in the Hogdon cowboy manual. Changing powders and reducing the charge weight solved that problem.

You are exceeding the velocity of factory J-word loads.

Shiloh
12-12-2007, 01:06 PM
Great Photo. Reminds me of some footprints I saw on a bar room dance floor once.

Shiloh

buck1
12-13-2007, 06:21 PM
You dont by some chance have a very leaded bore do ya? I'm just guessing.....Buck

garandsrus
12-13-2007, 08:27 PM
Buck,

Nope... I shot the loads in the 30-30 cases at the beginning and the end of the session to get a benchmark at the beginning and show that the bore wasn't leaded at the end.

John