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View Full Version : Gas check over PC does anything???



Maximumbob54
07-29-2015, 07:39 PM
I've not defeated the PC yet with any kind of velocity in pistol or rifle. So this has nothing to do with that issue.

My question is if a GC does anything for the accuracy of any loads tested so far. In the past I've been guilty of trying to plink for cheap by shooting GC bullets without the GC and quickly find accuracy suffers with velocity. Adding the GC back again and the accuracy comes right back.

So my question is this... Would adding a traditional or plain base GC to a PC bullet do anything fro accuracy?

It will be a while before I can test this theory on my own but I do have some PB GC's installed on an already decent shooting bullet to see if the group tightens up any. But I don't have a mold that drops both a regular and GC version for the exact same bullet.

bhn22
07-29-2015, 08:32 PM
The gas check also acts as a wrench of sorts, giving the bullet a better grip to the rifling than plain lead. It also gives the bullet a uniform flat base at the rear of the bullet, the steering end. The bullet base needs to be flat, and perpendicular to the bullets axis or accuracy suffers.

Smoke4320
07-29-2015, 08:37 PM
On 308 I was able to get to 2100 fps on gc bullet but no check after that accuracy went away adding a check and I went to 2400 fps
Virtually the same with 358 win

sixonetonoffun
07-29-2015, 09:13 PM
This is good info. Can GC/PC make it to Jacketed velocities then on a big bore since most of them are going to be hitting full power loads @2400-ish ?

bhn22
07-29-2015, 09:56 PM
Accuracy suffers unless you do all of your load development. PC is not a license to steal, it simply adds a coating between the bullet and the bore.

bstone5
07-29-2015, 11:18 PM
A gas check on cast plain base bullet that have been powder coated can be loaded at any safe load. The combination will work on all cast pistol bullets.
I make the gas checks from Cola Can material .004 inches thick or from roof flashing .010 thick.
The thicker flashing grips better on the lead bullet.
It is possible to shoot several hundred rounds and end up with zero lead in the barrel.

popper
07-30-2015, 09:59 AM
Coating is like an M&M, the inside needs to be tough enough to take the pressure.
gives the bullet a uniform flat base at the rear of the bullet, the steering end. I've run PB to 1800, GC to 2750 in 308W but my alloy is nothing standard.

sparky45
07-30-2015, 10:25 AM
What I've found is that the GC firmly stays in place when I PC after putting on the GC. I put the GC on when I size the bullet and again after PC, although I probably don't need that last sizing. So far, no keyhole on target.

sixonetonoffun
07-30-2015, 10:26 AM
I wonder about the zinc washer approach. Haven't found much data on that though.

Popper have followed your posts with interest. Seems the harder alloy is working for you. What is your opinion on combining a soft well made tip? Can it be done and maintain the balance and consistency desired at a moderately high velocity? I realize the time invested would keep most from this rabbits hole... but I feel drawn towards it.

Though swaggering might be simpler approach.

popper
08-03-2015, 12:45 PM
combining a soft well made tip? Don't know, haven't tried it as I shoot for entertainment. It is a very valid question, I've thought about recently. I'm shooting a slick sided rifle boolit that is not a bore-rider in the normal sense. Lots of drive band area but it still needs a hard alloy for accuracy at HV (308W). 170 gr. RNFP GCd, some front band is in the freebore. The opinion I'm getting is nose slump problem with softer alloy. At some pressures, the slump helps, too much and the nose deforms enough to lose accuracy. IMHO the reason the RD works so well, slump fills out the bore, nose can't deform. A two stage pour, soft nose/hard body might work or the torched nose. Haven't tried either.

gunoil
08-04-2015, 07:48 PM
gc's improved my pistol plinking big time instantly. l shoot with both eyes wide open.

StromBusa
08-06-2015, 01:05 PM
Spray coating over gas checks makes for an easy release from the aluminum foil

runfiverun
08-06-2015, 02:31 PM
you need to define your goals with/and your particular situation.
high velocity hunting is not going to benefit from a soft nose unless you just want to tear up on some prairie dogs.
high velocity is also going to be more sensitive to slight imbalances in the boolit.
high velocity with cast is not going to happen with a Band-Aid, you need a knowledge base, Time, and will have to accept some failures.

define your goals and look at realistic out comes for each avenue.
cheap isn't always a viable alternative, and actually buying pre-made stuff from a store is sometimes actually the cheapest best way to get what you want.