best accuracy?

[mainiac]

Is it my imagination, or have my best groups always been with gas check boolits? Upon looking at all of my load data, about every gun has shot the best groups with checks. Is this normal with you folks, and if so, what is the single best reason that this is so? Ive dug many hundreds of plain base boolits out of the sand,and they appear to still have very square bases on them. I want to get away from checks,but im also always looking for top accuracy. Are the bench-rest schuetzen fellers allowed to use checks?

[44man]

I can only speak about revolvers. I will say no for them as I get as tight a group with PB boolits. More depends on boolit design then what is on the bottom.

[shooter93]

Either type will or can shoot as well as the other, it's a matter of fit, lube and velocities...and a myriad of other things.

[shooter93]

And no...Shuetzen shooters can't use gas checks.....CBA has both classes.

[jack19512]

Is it my imagination, or have my best groups always been with gas check boolits?







I haven't been casting for that long but from what I have experienced so far I would have to say that is what I have found also.

[Bass Ackward]

Is it my imagination, or have my best groups always been with gas check boolits? Upon looking at all of my load data, about every gun has shot the best groups with checks. Is this normal with you folks, and if so, what is the single best reason that this is so? Ive dug many hundreds of plain base boolits out of the sand,and they appear to still have very square bases on them. I want to get away from checks,but im also always looking for top accuracy. Are the bench-rest schuetzen fellers allowed to use checks?


Biggest reason? More human proof. The base is the steering wheel of the bullet. From beginning to exit, a gas check is easier to reload well and offers a wider pressure range to shoot.

If you can increase your number of accurate loads, then chances are, one of those accurate loads will turn out to be more accurate than the rest.

But most people that have problems WITH PB bullets, usually damage their PB bullets in the reloading process.

[pdawg_shooter]

Get my best accuracy from paper patched boolets. With or without checks !

[1Shirt]

In rifles above 1200 fps or so, it has been my experiance that I need a gas check blt. Up to that point, or even a bit faster have had good luck with PB blts. Then of course there is the factor of a satisfactory lube and proper sizing with either PB or GC.
1Shirt!:coffee:

[jonk]

I have found it to be the case as well but don't shoot many without gas checks for rifle. For pistol I've not yet shot one WITH a check so who knows...

[mag_01]

:coffee: ---- Don't overlook a filler as your solution --- I have had good luck with ground walnut (solid type filler) giving me about same group size as gas checked boolits load for load and boolit for boolit --- The round tested was 7.62x54R ---- Keep in mind fillers raise pressure so use reduced loads and work up. If I remember correctly the load was 16 to 18grs. of 2400 and a 185gr. boolit (leave no air space) slight compression is ok -- Be careful if you go this route -- start lower--- Mag_01------ :castmine:

[lovedogs]

From what I've seen and what seems to be a general opinion I think usually it's easier to get accuracy and velocity without leading using GCs. But if everything is right; alloy, sizing, lubing, bullet design, etc., then PBs work real well, also. It kind of depends on what my goals are which kind I use. For purely target bullets I use slow loads and PBs with a soft (20:1) alloy. For hunting I use GCs and then adjust my alloy according to the velocities I'm shooting. I do real well using 20:1 alloy with GCs to almost 1500 FPS, past that I use a Lyman #2 alloy.

[Maven]

The results you see below were obtained with PB CB's in my .30-06 and Marlin .45-70 (Microgroove) @ 50 yds. The .30cal CB was a tapered (by me) group buy Lee #30-150-TL-PB, while the other was a LBT ~465gr. PB sized to .459". My '06 will group gas checked CB's into 1" if I do my part, but at 100yds. The Marlin isn't quite as precise, but it will group into 1.5" - 2" with PB CB's. The one heavy GC'ed CB I had for it (since sold) was capable of 1 moa in that rifle. Btw, it took quite a bit of fiddling with both powder charge and lube to get the group buy .30cal. CB to shoot well. Tapering it was the icing on the cake. In sum, I think gas checks allow greater velocity AND better accuracy with CB's wheras their PB brethren can be [as]accurate, but at the expense of velocity; i.e., at least in rifles.

The .30cal. target is on the right and shows 10+ shots.

[Ben]

I usually shoot gas checked .30 cal. bullets, however for plinking and informal paper punching I've become interested in plain based .30 cal bullets in the 1,000 - 1,400 fps zone.

Look at this 5 shot group that I fired @ 50 yards with my Springfield 1903 with Lyman 48 and 17-A front chambered in .308 Win.

Shot with Lee 200 gr, RN cast plain based bullet , no gas check ( I drilled out the gas check shank with a .311 drill bit in my drill press )

Bullets sized .3105 "

http://img.photobucket.com/albums/v494/haysb/12%2018%2007%20Range%20trip/PICT0007.jpg

http://img.photobucket.com/albums/v494/haysb/12%2018%2007%20Range%20trip/PICT0014.jpg

http://img.photobucket.com/albums/v494/haysb/12%2018%2007%20Range%20trip/PICT0012.jpg

[Blammer]

I have had good luck and good accuracy with both GC and PB bullets equally.

so I have no opinion on which is better. :)

[Ben]

Let me clarify something.....I'm not saying plain based bullets are better than g/c'd bullets ....or vice/versa. I only won't to show that when the necessary conditions for good accuracy have been met with plain based bullets that they will SHOOT !

Some people believe that plain based bullets in a 308 WIn. or a 30 / 06 are a waste of time, powder, and primers. That HAS NOT been my experience with plain based bullets.

Ben

[Bass Ackward]

I think it's great to see support for PB bullets.

All a GC is, is a harder base to increase your chance that your base survives the pressure you just put it through, so that it exits the muzzle square.

[405]

maniac,
I can only speak to my own experiences in shooting lead. Keep good load records, groups size records for each load, etc. And, trust your data and your gut.

Generally, I can just about guarantee that before a shot is fired out of a new-to-me (mostly old) rifle, after slugging and evaluating the twist rate..... that a GC bullet will shoot more accurately than a plain base. I can also just about guarantee that in those rifles that are designed to shoot jacketed (more modern, smokeless, etc.) that jacketed bullets will shoot more accurately than either plain base or gas checked.

I've found a few exceptions along the way.

1) both Sharps rifles I shoot will equal jacketed bullet accuracy and will always exceed plain base bullet accuracy with properly sized, swaged paper patched bullets

2) most revolvers I shoot with soft cast plain base bullets or factory swaged plain base bullets (Hornady) will usually equal jacketed bullet accuracy when loaded with faster powder at lower velocity.... 700 +/- fps

3) some of the older cartridge and gun combos like 38-40 in Colt Bisley, 38-40 in Win 92 and Win 73, 44-40 in Win 92 will shoot soft cast bullets or factory swaged plain base bullets (Hornady) with accuracy so good that there is little need in trying anything else. These are loaded similarly to the revolver loads.... faster powder and lower velocity.... 650 +/- fps in the Bisley and less than 1000 fps in the rifles.

4) with care, when applicable and using the best pressure data available I've found poly fiber filler over light charges of appropriate smokeless powder in certain straight walled case cartridges to give better accuracy than the same loads minus the poly filler in both plain base and gas checked bullets. I tend to believe two things are going on at the same time. The poly is protecting the base and the standard deviations of velocity and pressure are improved.

5) I don't shoot gas checked bullets in revolvers. Gas checks can detach from the bullet and lodge in the barrel.... particularly with light loads.

I think BassAckward has alluded a few times as to what is likely hard fact and that is.... even if the bullet gets down the bore OK there is one last destructive incident about to happen. Just as the bullet's base leaves the crown of the muzzle there is still a lot of gas under pressure wanting to escape. If the base is distorted since birth or during any part of it's journey the gas will escape in a jet at a weakest point and there is no hope for accuracy. Likewise, if there is a large charge of slow, progressive type powder behind the bullet the pressure will be extreme even as the bullet reaches the muzzle. Even a bullet with a perfect base as it leaves the crown has a hard time withstanding the gas. The hardest cast plain base bullet will have a BHN hardness of 20-30. Since the gas check is basically the same material as the jacket of a jacketed bullet (about BHN hardness 100... copper) the base has a better chance of surviving the trip.