.30 XCB wildcat, from scratch.

[MBTcustom]

Cool,
Thank ya Gentlemen for the info, I once spoke to Goodsteel about that reamer not for this project he was not certain exactly which one I was referring to hence is why I posted it in a question.

Well for one thing, whoever designed that chamber gave it almost .100 freebore, which was firmly decided not to be featured on the 30XCB chamber.

[lar45]

So far the results have been quite surprising and positive. Really looking forward to playing with this cartridge a bit.

+1 on that.
I have an extra 98 Mauser in 30-06 laying around that never gets shot and also a Winchester M1917 that could be a possible organ donor for the project. Which one would be the better platform to build on, or should I just get a new Savage and start with it?
My useage would be a sporter weight rifle to use for hunting and informal target work.
Oh I just remembered that I have a nice Huskavarna 270 that could use a new outlook on life.
???... . . . Hmmmm tooo much to think about.

Oh, another question. Would any of the factory stock barrels be worth reuseing, or should I just splurge for a new barrel to start with?
My good ol-trusty M98 06' can turn in some good results when I do my part

[Bjornb]

+1 on that.
I have an extra 98 Mauser in 30-06 laying around that never gets shot and also a Winchester M1917 that could be a possible organ donor for the project. Which one would be the better platform to build on, or should I just get a new Savage and start with it?
My useage would be a sporter weight rifle to use for hunting and informal target work.
Oh I just remembered that I have a nice Huskavarna 270 that could use a new outlook on life.
???... . . . Hmmmm tooo much to think about.

Oh, another question. Would any of the factory stock barrels be worth reuseing, or should I just splurge for a new barrel to start with?
My good ol-trusty M98 06' can turn in some good results when I do my part

Glen,
both the actions you describe would work fine as a platform for the 30X57 cartridge, but the Mauser 98 is already made for a 57mm round, and is therefore IMO the better choice. As for barrels, both your rifles probably have fast twist (1-10 barrels) that will preclude you from getting good accuracy at much over 2000 fps due to excessive RPM. The rifle that Tim is currently building for me is being made on a Small Ring Mauser (Oviedo 1916), using a Lothar Walther barrel with a 1-14 twist.

[runfiverun]

you guy's are starting to give my 308 a complex and make it think it cannot possibly break the 2400 fps barrier with it's 10 twist barrel.

I'd pick out an appropriate barrel weight for your purposes and go with the stock most suited for the job.
my next one will be strictly for hunting type purposes too, based on flinging 150 gr jacketed bullets around at 4 legged stuff instead of a dual rolled rifle like this one.

[Bjornb]

you guy's are starting to give my 308 a complex and make it think it cannot possibly break the 2400 fps barrier with it's 10 twist barrel.

I'd pick out an appropriate barrel weight for your purposes and go with the stock most suited for the job.
my next one will be strictly for hunting type purposes too, based on flinging 150 gr jacketed bullets around at 4 legged stuff instead of a dual rolled rifle like this one.

In no way am I trying to give your 308 a complex, and if she shoots lead accurately at 2400 fps so much the better. My advice to Glen/Lar45 was just based on my own experiences with fast twist barrels. I'm currently trying to tame a Ruger Gunsite Carbine; so far she's sub MOA with SMKs and minute of Pie Plate with anything lead. No offense was meant; be sure to tell your rifle.

[Larry Gibson]

lar45

+1 on the Mauser action. I'd suggest a new 26" barrel with a 14" twist. with that 2600 + fps should be very doable with the 30x57 (30 XCB) cartridge and a 155 - 165 gr cast bullet. Right now the 311466 and the new NOE 310-165-FN bullet are the best bullet choices. The 14" twist will adequately stabilize cast bullets of 185 - 200 gr also if heavier for hunting is a consideration.

The jury is still out on the 16" twist. You might wait a few months until I get mine up and running before investing in the new barrel.

Larry Gibson

[lar45]

Thanks for the advise.
I'm headed to Idaho to hunt Elk the end of October in R5R's back yard. So It will be a couple months until I can get things together.
Right now i'm just trying to get enough lube poured ahead to keep the orders going out to cover the couple of weeks I'll be gone.
Which of the barrel makers would be best for cast boolits?

[runfiverun]

I like an equal number of lands and grooves.
and a bit taller lands to bite into the lead a bit better.
Lilja has a good reputation amongst cast shooters B.T.W.

if I could figure out who builds the barrels for Armalite I would be ordering a blank from them [san's the chrome lining of course] for my next adventure.

[MBTcustom]

I agree with Lamar about taller lands being a nice feature if you have the option. However, that is not top of my list for desirable features on a barrel, and you will be hard pressed to find any barrel that is anything other than .300/.308.

The priority of QC falls on these points:
It must be consistent in diameter end to end. Both bore and groove. (Progressively tighter towards the muzzle is acceptable.
It must be consistent in twist end to end. (Progressively faster is acceptable).
It must be STRAIGHT.
This last requirement I impose on cast boolit rifles much more than I do on a rifle meant for jacketed, but for superb accuracy, I demand it regardless of what I am shooting. I believe it has a much more noticeable effect on cast than jacketed.
i have received barrels with "hook" from Shillen, and Lilja. So far, not from Green Mountain, Bartlien, Douglass, or Lothar Walther.
By far, the best quality barrels that have come through the shop have been from Krieger, with Lothar Walther being the runner up.
Krieger is superb in all aspects of barrel quality, and I trust them implicitly. They stand behind their product too. If I am building for precision, it's going to start with Krieger.

BTW Glen. I am casting NOE XCB boolits every Sunday, and once I have a stock of them in every alloy I need, I will let you borrow the mold. This truly is a fun boolit to shoot. I ran eight through my 10 twist XCB last weekend, and the results were fun. Much better than anything I have tried thus far (not that that's saying much). It's a real easy boolit to work with.

I'm going to try it with PC and 45/45/10 someday.

[detox]

goodsteel, How do you check a barrel for straightness? I did a search and read that some can look thru the bore and tell.

[tomme boy]

Spin it and look for shadows. It takes a very keen eye.

[Larry Gibson]

Numerous barrel makers make .30 cal barrels with 14" twists. Usually, as Tim mentioned, they will be of .300/.308. With the 14" twist I would look at 4 lands and grooves with the lands covering 30 - 35% of the bore, pretty much the standard military and commercial configuration.

Since the barrel is paramount to accuracy I suggest getting the best quality you can afford. As to which maker's barrels is "best" with cast bullets? I have used match grade Kreiger, Shilen, Douglas, Pac-Nor, Llilja (SP?), Lothar-Walther, Schneider and factory barrels with equal success. My current 14" twist Palma barrel is a Schultz & Larson factory barrel.

Some custom makers offer different rifling and use the cut method. The can give you different bore/groove dimensions but you really pay for that. My ordered 16" twist Broughton barrel is such. In the end if you really want the "best" then plan on paying for it.

Larry Gibson

[MBTcustom]

goodsteel, How do you check a barrel for straightness? I did a search and read that some can look thru the bore and tell.

And that is how I do it as well.
I trained myself to do this by looking through superbly straight tubing, and then bending the tubing a known amount (measured on a surface plate with test indicators) and looking down the tubing. I can accurately judge straightness of a barrel within .005 accuracy between .005 and .030 hook. Takes a while to get your eye trained, but once you know what you are doing, it becomes no harder than judging distance to a target, or the height of a tree etc etc etc.
if anyone wants to learn how to do this, and need a source for perfectly straight tubing, look up Easton X-7 arrow shafting. That is a common and available source for 32" tubing that is guaranteed straight within .001 inches.

I might also add that I called all the major barrel manufacturers and asked what their tolerance for straightness is. Each one told me I was the first person that had ever asked them that question, and had to refer me to the floor manager to get me an answer.
Kreiger was the quickest response (imagine that) holding that they insist on a straightness of less than .002 inches end to end.
Shilen was the only manufacturer who did not answer my questions at all.
I did not call McGowen, as I will not use their barrels in my shop.

[runfiverun]

I have been to the Easton factory.
they eyeball them..
they shoot them in the hallway too, but they straighten their shafts by eye.

[detox]

I received my aluminum 2 cavity version of this NOE mold and casted a few bullets using straight linotype. Bands measure .3124 and with only .0005 run out....this is my most round mold....very good! Taper appears to be about 1.0- 1.23 per side...not sure. I believe this bullet will be a winner in long throated factory 30 caliber rifles.

308 Cartridge on left was chambered in re barreled Remington 700 with fresh cut minimum 308 SAMMI chamber (.090 freebore). Bullet was pushed back in case when chambered. Barrel is Shillen with 1/10 twist, wide six groove rifling. This barrel usually shoots good using good fitting bore ride bullets.

308 Cartridge on right was chambered in Remington 700 VS with worn 308 NATO chamber. (.150 freebore). Bullet was engraved, but not pushed back when chambered. Factory barrel with 1/12 twist and narrow six groove rifling. This gun shoots bore riders and taper nosed designs well. I believe the NOE bullet will work verywell in this barrel also.

IMO this bullet will work verywell in most factory chambered 30/06 rifles (if sized to fit free bore).

[MBTcustom]

Detox, the XCB boolit was designed to be seated just a touch deeper than what you have there on the left. I believe if you took OAL measurements with a gauge like Hornady makes, you would find this to be true.
The way I designed it, there are actually five driving surfaces including the GC.
The GC driving band is .075
The next band forward is .064
The subsequent three are .055
However, you can't really see the last one as it transitions to the leadin angle. Still, it is .055, and should be treated as a driving band.
If you get in a habit of jamming the XCB boolit into the lands, and that leadin angle actually matches the XCB chamber, and your chamber is actually straight, you may have problems leaving Boolits in the barrel when the cartridge is extracted.

[detox]

I under stand you designed the bullet for your custom chamber, but I believe this bullet will work very well in factory chambers also. When I go to the range I will post pics of my targets.

Not pictures of just one good group, but pictures of 10 five shot groups or 5 ten shot groups.

[MBTcustom]

Yes, I know. I have had good results in my 308, 30XCB, and my Savage 340 C (will be testing in the M1A soon as well and I expect excellent results forthwith).

The boolit is very well ballanced. I was just pointing out that it seems to be exceptionally well suited for your 308 (pictured on the left) as designed, and if I jammed my boolits into the rifling like that, the XCB cartridges would look very similar in seating depth. Should do exceptionally well in that rifle.
That's all I was saying. I appologize for mot being more clear. I was in a hurry when I typed that (and still am) and I missed what I was trying to convey. Sorry.

[runfiverun]

I made up a dummy round with one of my reject boolits and tried it in a couple of my 0-6 rifles just to see how it felt.
the seating depth of just covering the front lube groove worked in all of them.

anyway I wish that front lube groove was left off.
it isn't necessary to use anywhere near that much lube and the extra lead would come in handy when shoving things forward.
I just re-set the star to lube the bottom two lube grooves. [so no big deal]
I'll just go with the bottom one and a softer lube if I decide to just lump things along at 1900 or so at some point.

yeah it will work in most 30 cal factory rifles pretty well.
i'll have to size a 308 case or two and see how my tight throated rifles take to this boolit.
is so good, if not [shrug] I got one cut for them already.

[Larry Gibson]

anyway I wish that front lube groove was left off.
it isn't necessary to use anywhere near that much lube

That much lube is needed if you remember the one of the primary criteria for the 30 XCB bullets design; velocities at 2600 - 2900 fps. There is a similar .30 cal cast bullet (LBT 30-160) with one slightly larger lube groove and a a bit of lube in front of the GC. It falls short on lube in the 2400 - 2500 fps range. That was the reason for the 3 minimally sized lube grooves on the NOE 30 XCB bullet; the grooves are minimally sized in both width and depth to maintain maximum bullet strength yet to carry enough lube for the higher velocity. If one wants to lumber along at the normal for most cast bullets velocity of 1600 - 1900 fps then it really isn't any better than most any other 160 - 170 gr .30 cal cast bullet design.

Shot my NOE 30 XCB bullets in my Palma .308W rifle at 100, 200 and 300 yards yesterday. Load was the 2600 fps one with AA4350. Shot two 10 shot groups at 100 yards; both were in the 1.6" range. The wind was really nasty gusting 7 - 12 mph and switching coming out of 10 to 1 o'clock inconsistently and you can see the horizontal dispersion. I still managed a 1.75 moa 10 shot group at 200 yards and a 2 moa 10 shot group at 300 yards.

The 30 XCB cast bullet was designed for maximum top end performance. The 30x57 (30 XCB) was also designed for top end performance with a cast bullet. Both were designed for velocities in the 2600 - 2600 fps range, specifically with a 14" twist barrel. If we put the NOE 30 XCB bullet in other cartridges with faster twists we will, if we cast and load correctly, see enhanced accuracy at higher velocities than normally expected with cast bullets for those cartridges. However, if we dumb down the velocity, (perhaps not the best terminology but you get the meaning) then neither the cartridge nor the bullet will perform better than any other quality design from a quality mould.

It's not really too hard to take anything outside it's design criteria and criticize it. If we keep the NOE 310-165-FN bullet with in it's intended design criteria it excels. Same with the 30x57 (30 XCB) cartridge. Outside of it's design criteria it really isn't better than several other cartridges.

We must note though that one of goodsteel's additional criteria for the cartridge has been to give it as best possible concentric alignment in tuned and well bedded actions for maximum performance. I've no doubt that if he did the same with similar 10" twist rifles of .308W, 30 XCB and 30-06 that in the end, even with the NOE bullet we would see pretty much identical accuracy potential at pretty much the same velocity.

The real "magic" of the of the NOE 310-165-FN's design is when it is used in a 14" twist or perhaps a 16" twist at higher velocity. The .308W can easily accomplish that objective to 2600 fps +/-. The 30x57 (30 XCB) and perhaps the 30-06 are the likely candidates for the 2600 to 2900 fps objective.......but only with the slower 14 or 16" twist longer barrels.

Larry Gibson