Starting point needed.

[RTRDave]

greetings all...great site. I have been poking around and have not seen what I need yet.

A bit of back ground.

Barrel is a 1:14 twist. 458 cal. 20 inches long.....

It is a 458 SOCOM, but I don't want to buy bullets.....I really don't even want to buy gas checks. I bought it because it throws a big heavy bullet about the same as a 47-70 so I should be able to cast for it. BUt I can't find anyone yet that does it.

I do know that I can push a 300 grain HP remington copper jacket roughly 2000 fps. From what I understand this is too hot to run without a gas check....So the question is....where do I need to be velocity wise to run a cast bullet without a gas check?...........I know heavier will undoubtably stabilize as this is the same rate of twist I have seen in 47-70's........

I have the following data as well.

A 405 bullet pushed out at 1600 fps
A 500 bullet pushed out at 1400 fps

If I am gonna go slow I want big right?

If I run the 330 lyman with a gas check will I be ok around the 1900fps mark? or will leading irritate me?

Thanks for the starting point and your time

Dave

[Dale53]

In good barrels, you can drive a plain base bullet up to 1500 fps or so (with accuracy). You can probably drive a gas check bullet in a .45 caliber rifle to 2000 fps or so (some have excellent results far faster than that (typically in smaller calibers).

Dale53

[runfiverun]

that 405 at about 14-1500 sounds real good about what 45-70 bp ran, can easily be done with acww's also.

[montana_charlie]

I have no knowledge about the 47/70, but...
45/70 barrels with what is considered to be 'the fast twist' are 1 turn in 18 inches.
Some 45/70 guys are beginning to experiment with 1 turn in 16, when shooting the recently designed bullet from Dan Theodore called the 'Money Bullet'.

1 turn in 14 inches is 'pretty dang fast', I would think.
Might even require jacketed bullets...especially if the rifling is shallow.

20 inches long? Is that a Thompson Center barrel?
I have read some disappointing things (lately) about their chambers.
CM

[SharpsShooter]

Yep, 405gr cast at 1400fps should do it nicely

SS

[James C. Snodgrass]

:castmine:I've got a 1 in 14 on my Lott and have gotten good accuracy at that velocity with ww and 1% tin added and water dropped. Mine seems to stay good till about 1650 or so with plain based. Just my experience, James

[Johnw...ski]

My 45-70 is in a home built rifle with 1 in 14" twist and 26" barrel.
The 425 gr gas check boolits I have been shooting are the same as lyman 405 gr but heavier for some reason. they regularly shoot 1 1/2" groups at 100 yds., with velocities in the 1400-1500 FPS range.
The other boolit I have been useing, a lyman 457132 is a 535 gr plain base is also starting to show 1 1/2" groups at 1200-1300 FPS. Still working on a load for the 535 gr boolit, I'me sute I can do better than 1 1/2".

John

[RTRDave]

Thanks guys.....looks like I'll start with the 405 everyone seems to gravitate around. I meant 45-70 sorry for the confusion. The barrel is not a thompson, it is custom made by Teppojutsu specifically for this round. I have a mountain of wheel weights and can water drop them. This should make them good and hard right? I want to go with the flat base lee mold right?.....would the Hollow base tend to lead more?....

[runfiverun]

the hollow base is if you want to p.p or to cast from pure for b/p so it will bump up to fit the rifling.
thought the 458 was in an ar platform?

[RTRDave]

It is an AR platform, but the reason I ordered it is that it shoots a big bullet (up to 600 grains) and it is a reasonable velocity so I can cast boolits to shoot. If I don't cast them, I am looking at almost $.25 a projectile plus powder and primer. I figure if I can make a good hard cast boolit that I can get good accuracy out of, no matter what the wieght or style, it should be plenty to put down deer and hogs with inside of 150 yards and should be fun to shoot as well.

I applogize for my ignorance, but I don't know what p.p is or b/p....it won't be pure lead, just wheel weights. I am novice at this whole thing and am trying to start off on the right foot. I hate the idea of reinventing the wheel. You guys have done a pile of research and have a huge amount of experiance with all of this and I appreciate your thoughts. Once the gun arrives, I want to already have some loads made up so I can find the sweet spot.

[crabo]

Please keep us advised in your journey. I have thought about doing the same thing.

Crabo

[Buckshot]

...............On an AR platform. So this is a semi auto? Don't know about that, but I've driven PP 405 gr cast lead to 2000 fps and 500 gr slugs to 1800 fps in a converted MAS36, but it's a bolt gun and I think a 20" twist.

I have a 375-06 AI with w 12" twist. Normal for caliber cast shoots great to about 1600 fps. Going to 325 and 350 gr cast slugs it does pretty well to about 2000 fps.

..............Buckshot

[RTRDave]

buchshot.....your doing this "WITHOUT" gas checks?.......THat is fantastic. If that is the case then I should be able to do about the same. If mine is 1:14 and your 1:20 does that mean I need to back it down just a tad to keep from leading up the barrel and then work up?

Thanks

Dave

[mcassill6933]

It is an AR platform, but the reason I ordered it is that it shoots a big bullet (up to 600 grains) and it is a reasonable velocity so I can cast boolits to shoot.

I could be wrong, but I think you are going to run into trouble with lead bullets and the gas tube on those. They are not easy to clean metal shavings out of...
Mark

[MT Gianni]

[QUOTE=RTRDave
I applogize for my ignorance, but I don't know what p.p is or b/p....[/QUOTE]
PP=Paper Patch B/P = black powder. I can't see you using either of there in an AR. Gianni

[Buckshot]

buchshot.....your doing this "WITHOUT" gas checks?.......THat is fantastic. If that is the case then I should be able to do about the same. If mine is 1:14 and your 1:20 does that mean I need to back it down just a tad to keep from leading up the barrel and then work up?

Thanks

Dave

................A faster then required twist isn't good with cast lead. You can tighten the twist to a point, but then any more will be derimental to cast lead, re: my remarks about the 375-06. You have to back the velocity down.

................Buckshot