450Bushmaster.net

I want to try this one a 350 grain!
http://www.acmebullet.com/bullets-reloa ... NFP-CASULL

That would be interesting to try if the rifles twist will work with that heavy of a bullet.

With 350 grains you're leaving 444 Marlin ballistics and approaching a 45-70's. I don't know if one could duplicate the 45-70 velocity though.

Dan

Umm...cast/lubed boolits are really not a good idea in an AR platform IRT the gas port/gas block operating system. Stability, due to the standard barrel twist rate, is also very questionable with a 350-grainer IMHO...

I'm not sure how I missed ths post back on Xmas eve, but I noticed it now. I suspect you could accommodate that bullet in a bolt action 450b, but it will not come as easy in an AR variant. I can't speak from personal experience, but from what I've read from a few members here who have dabbled with them, cast boolits and their gas checks have a bigger challenge in an AR platform, with it's gas sampling port. Those ports can be sizeable in the rifle length gas system which would in all likelihood be the best choice for a 350gr bullet. Not a good matchup for a carbine length gas system as they're going to be spending a lot of time in the bore as they amble along. Then there's the challenge of getting a good grip on them crimpwise. Not to enhance the propellant getting cooking as with light bullets, but to help reduce the bullet pulling when they're chambered from inertia.

Sounds to me like someone has a great project to try out and report back to the group on. Those bullets would probably align well with AA 5744 or 1680 and Rem 7 1/2 primers.

The best part of the journey is getting there.

Happy New Year

Hoot

commander faschisto wrote:Umm...cast/lubed boolits are really not a good idea in an AR platform IRT the gas port/gas block operating system. Stability, due to the standard barrel twist rate, is also very questionable with a 350-grainer IMHO...

I may disagree about cast in a AR I have a 300 Blk out that I have mostly shot 203gr cast bullets 1000 rounds and counting so far it's been ok. These 350 grain bullets are plan base no gas check. I may test them out in the 1:20 twist 450BM if they don't work out I'll shoot them in my 454 BFR

PJames wrote:

commander faschisto wrote:Umm...cast/lubed boolits are really not a good idea in an AR platform IRT the gas port/gas block operating system. Stability, due to the standard barrel twist rate, is also very questionable with a 350-grainer IMHO...

I may disagree about cast in a AR I have a 300 Blk out that I have mostly shot 203gr cast bullets 1000 rounds and counting so far it's been ok. These 350 grain bullets are plan base no gas check. I may test them out in the 1:20 twist 450BM if they don't work out I'll shoot them in my 454 BFR

Have you looked in your 300 Blk barrel with a borescope?

Hoot

Hoot wrote:

PJames wrote:

commander faschisto wrote:Umm...cast/lubed boolits are really not a good idea in an AR platform IRT the gas port/gas block operating system. Stability, due to the standard barrel twist rate, is also very questionable with a 350-grainer IMHO...

I may disagree about cast in a AR I have a 300 Blk out that I have mostly shot 203gr cast bullets 1000 rounds and counting so far it's been ok. These 350 grain bullets are plan base no gas check. I may test them out in the 1:20 twist 450BM if they don't work out I'll shoot them in my 454 BFR

Have you looked in your 300 Blk barrel with a borescope?

Hoot

I don't have a bore scope but, I did have my gunsmith check it out with the scope. I pulled the gas block and all looked good. Bolt also has no build up after shooting 100 plus rounds. I was concerned about it but not anymore and what I have in the 300 blk money wise I'm not concerned to much if it ever goes to crap. Accuracy is still very good and it has been 100% reliable.

203's, so you're shooting the palmettos coated ones?

and in the blackout those are subs, so whole different world than trying to shoot these lubed bullets as supers without being gas checked.


i would be legitimately concerned about leading without running something like these with a gas check.


FWIW - avoid lil gun, i can tell you from my BLK experience that supers + lil gun + cast (even properly coated bullets) = spraying molten lead out the end of the barrel. its just too hot of a powder. Switching to 4227 fixed that issue.

i had to scrape a coating of lead off the blast shield of my magnetospeed bayo. bleh.

I tried cast bullets years ago. What Hoot states is a solid summary. My issues were as follows:
1. Barrel Gas Port is LARGER than the depth of a gas check. The gas is expanding 2 to 3 times the velocity of the projectile in the barrel. When the gas check passes by the gas port, the gas comes around the check and dislodges the gas check on the bullet. I have pictures located somewhere on the forum. Also, of all the numerous lead bullets I collected ---- none of them had an intact check.
2. It is imperative that a gas check be used (although see above). Without the check, the gas would cut a divot in the base of the bullet as it passes the gas port. Although I never shot coated bullets ---- that would be an interesting test.
3. The 1"x24" twist is not conducive to accuracy with longer bullets.
4. With 300 grain WFN bullets I had significant slumping of the bullet nose. The profile changed and the bullet became shorter. The abrupt rise in pressure at ignition seems to be the culprit.

All these issues are the primary reason I just purchased the RAR in 450B. That rifle has a 1"x16" twist. Should handle the longer lead bullets just fine.

Often in the evening, I find myself slumping at the computer. I suspect it is from starting out the day too fast. Sorry John, couldn't resist.

Hoot