Gas Checks May Soon Be Only a Memory
- Thread starter quicksylver
- Start date
35 shooter
Well-Known Member
Question..
Would using a slower bbl. twist such as 1/38 in 357 or 44 cal. aid in shooting pb faster than usual?
I noticed a thread on another site in which a guy claimed shooting pb in his 357 mag. lever action at pretty much full velocity with light to med. weight bullets.
He attributed the results to the slower 1/38 twist.
Would using a slower bbl. twist such as 1/38 in 357 or 44 cal. aid in shooting pb faster than usual?
I noticed a thread on another site in which a guy claimed shooting pb in his 357 mag. lever action at pretty much full velocity with light to med. weight bullets.
He attributed the results to the slower 1/38 twist.
Gary
SE Kansas
What?? Are you saying you wouldn't/don't shoot Lead in your AR or you wouldn't shoot Lead WITHOUT a GC? Again, I only shoot PB 247 gr NOE @ roughly 1080 fps. and without a GC. Open gas port and I haven't seen a problem, yet.
quicksylver
Well-Known Member
I came to that conclusion through the back door...cut mine then bought new DBL cavity PB...oh well......enjoy they work great...
quicksylver
Well-Known Member
IMO ..the slower the twist the faster you could push them...as a mater of fact with heavier bullets you would have to..
The difference between 10 and 12 is amazing to me in 30 cal..
Ian
Notorious member
I shot mountains of PB subsonics in my Blackouts, consistent 1.5" ten-shot groups at 100 yards from three different rifles fed from the magazine, but the gas rings always got leaded up after a hundred rounds or so and I got really sick of scraping lead off the suppressor baffles. Powder coating solved all those problems.
All that got me to thinking how much lead dust is blown out of a muzzle. I never got bore leading in the blackouts, not even a little bit, but no matter the alloy, bullet size, or lube, the gas rings and suppressors always got fouled. Never did try a gas-checked bullet, mainly because I didn't want to risk them coming off in the cans. Just because you aren't getting bore leading with a plain-based bullet doesn't mean you aren't generating a lot of lead dust from the shot.
As to those shooting plain-based bullets at high speed, it can be done. I've pushed plain-based .44s to over 1400 fps in a revolver with great accuracy way on down range. Same with .45 Colt. I'm not sure at what point a gas check would be required to prevent lead fouling or maintain accuracy at longer ranges in a .357 Magnum or other straight-walled cartridge, but probably only at the very top end.
All that got me to thinking how much lead dust is blown out of a muzzle. I never got bore leading in the blackouts, not even a little bit, but no matter the alloy, bullet size, or lube, the gas rings and suppressors always got fouled. Never did try a gas-checked bullet, mainly because I didn't want to risk them coming off in the cans. Just because you aren't getting bore leading with a plain-based bullet doesn't mean you aren't generating a lot of lead dust from the shot.
As to those shooting plain-based bullets at high speed, it can be done. I've pushed plain-based .44s to over 1400 fps in a revolver with great accuracy way on down range. Same with .45 Colt. I'm not sure at what point a gas check would be required to prevent lead fouling or maintain accuracy at longer ranges in a .357 Magnum or other straight-walled cartridge, but probably only at the very top end.
35 shooter
Well-Known Member
Ok, thanks for the replies on the slow twist shooting pb. I was just thinking about the 1/38 twist in 44 mag. and thought it might work really well for faster pb speed shooting up to 200 ,250 gr. bullets with accuracy and no leading.
I know alloy and powder type and bullet fit go with all of this too. The post on the 357 mag. was using lil gun and getting 1700 to 2000 fps. with the lighter pb bullets of 158 gr. and down. I can't get anywhere near that in my 1/14 twist 35 whelen.
I'd never use checks with that kind of performance. Very interesting.
I know alloy and powder type and bullet fit go with all of this too. The post on the 357 mag. was using lil gun and getting 1700 to 2000 fps. with the lighter pb bullets of 158 gr. and down. I can't get anywhere near that in my 1/14 twist 35 whelen.
I'd never use checks with that kind of performance. Very interesting.
quicksylver
Well-Known Member
I should think the style or type of rifling would also be important...
RBHarter
West Central AR
My best load in a 358 Win was at 2100 fps with an RCBS 35-250 FP but that is checked . I never had any trouble running whatever the alloy would hold in 357 but I never went to the top of the top if it shot good in the pistols it was better and 400 fps faster in the Marlin CB.
In 30 cal PB about 1800 was all I could get but I was working in 9+ twists mostly .
I know a gentleman that has run checked 30 cal in twists as slow as 1-16 accurately up to 3000fps . Over and over .
In 30 cal PB about 1800 was all I could get but I was working in 9+ twists mostly .
I know a gentleman that has run checked 30 cal in twists as slow as 1-16 accurately up to 3000fps . Over and over .
Interesting point. Recently had to clean the gas key in the BO. Then I checked the carbine (308) that has just GC throuht it, clogged also. Rifle key (308 GC) wasn't clogged. Hmmm. All PCd. My guess it's PC dust from the higher port pressure at shorter length. Same load in the rifle & carbine. Gas tube & block are fine on all. I'll watch the pistol port one for problems. Increased the 170PB load for the 30/30 to see where it goes to pot. I've a terrible anticipation flinch at the bench (not in the field), my 30/30 target groups got better when I tried to avoid blinking, recoil 'push' and watched my breathing & trigger pull.
Ian
Notorious member
Popper, I meant UNcoated plain based is what I was having problems with. Never had a gas key foul up, ever, no matter the bullet type/coating/checked/PB/boat tail etc., but I don't do supersonic Blackout loads. Gas rings, bolt tail, and the bottom of the bore in the bolt carrier are where I got all my lead buildup with uncoated, grease-groove, plain-based bullets.
My bolts are usually pretty clean, just carbon buildup, not much. IMO lead or PC dust or lube, it gets 'dumped' where the velocity drops or direction changes. I purposely leave the PC off the base for better accuracy. Some claim there is gas cutting on the base due to the port - that should automatically cause poorer accuracy. Might happen with pistol port or subs, don't see how it can happen with supers but that could be the difference between rifle & carbine gas - higher fps for the rifle.
Ian
Notorious member
I have recovered multiple bullets from gas guns and at subsonic speeds, it takes a 20x machinists loupe to even detect where the bullet passed the port. I think it's insignificant. My AR-45 has a 1/8" gas port located in the throat area, maybe 1/4" ahead of the chamber, and it barely marks the base corner plain lubricated bullets and doesn't wash any metal out.