Cast Boolits drifting out of case ?

[pt4u2nv]

I have been working up loads and using different boolits for my 357 SIG and have moved up to a .358 sizing die on the Lee 356-125-2R boolit to try to stop a keyholing problem. ( .356 and .357 sizer did not stop the keyholing)

Bore slugged at .3551 and even the .357 sizer only gave me a .3562 boolit along with major keyholing.Tried 3 different powders AA5, AA7 and Unique at various loads..still keyholing bad at 15 yds. Used straight WW for alloy and up to 50/50 mix WW / Pb with tin added in all the different combos and none of them stopped the keyholing.

When I seat the boolits ( sized with .358 sizer, .3571 actual dia.) at 1.140" and set them aside to taper crimp them later they creep back out of the case to as long as 1.175". I am assuming it is because the larger boolit is not letting the air out of the case and it is pushing the boolit back out to relieve the air. They are not too large as to expand the case neck but this is a royal pain in the butt. I have had to reseat them as many as 3-4 times to get them to stay put and then I better not waste any time switching to the taper crimp die. I would like to move over to my progressive once I get a good load worked up but this will never happen if I have to continue to go thru this ordeal. Any suggestions or comments will be greatly appreciated.

[pistolman44]

I had a simular problem. I was using nickle plated brass and couldn't get a tight taper crimp even using a seperate taper crimp die. I bought some plain brass and it cured that problem for me. I'm no expert but it seems to me now that the nickle plated brass was springing back a little after crimping.

[mike in co]

why not do it in your progressive now ??
just skip the powder measure( i'm assuming you are doing individual powder weights).
seat and then crimp......
i use my dillon 550's that way all the time.....i seldom use a single stage press.


mike in co

[pt4u2nv]

why not do it in your progressive now ??
just skip the powder measure( i'm assuming you are doing individual powder weights).
seat and then crimp......
i use my dillon 550's that way all the time.....i seldom use a single stage press.


mike in co

The boolits are creeping out fast enough that I am sure some will be too long before they rotate to the next station. Some seem to stay put and others will drift out. I have to reseat them several times before they stay where I seat them.

[Glen]

Is your powder charge compressed?

[pt4u2nv]

I had a simular problem. I was using nickle plated brass and couldn't get a tight taper crimp even using a seperate taper crimp die. I bought some plain brass and it cured that problem for me. I'm no expert but it seems to me now that the nickle plated brass was springing back a little after crimping.

All my cases are brass so not sure if that is the case in my situation or not. Mine stay put after they are crimped, it is just the time from seating to crimping that they move.

[pt4u2nv]

Is your powder charge compressed?

No, it is not compressed, I never even got close to max loads on any of them yet.

[fredj338]

No, it is not compressed, I never even got close to max loads on any of them yet.

In 30+ years of reloading, I have never seen this happen unless loading over extremely compressed charges. There is not enough cpmressed air under the bullet to force it out of the case. Something isn't right w/ the sizing die or maybe expander. Personaly, taper crimping rev rounds isn't ever going to give the best result, especially under recoil. Roll crimp those bad boys.

[lwknight]

I've not heard of this phenomenon either but was thinking that using the roll crimp in the bullet seater die might help.

[ANeat]

Sounds like you may be expanding the case too much before seating. You should have enough neck tension even before crimping.

Measure the diameter of the expander where it enters the case.


I see Fred mentioned the expander earlier as well ;)

[Bwana]

That's pretty strange. Been loading for 40 yrs and haven't seen that or heard of it. I don't know what kind of "sizer" you're using, I suspect Lee push through if your finished sizes are off that much; unless it's your caliper or your reading of your caliper that is off.
I use the Kead 125 TC BB (sized .358) in my G32 and have no problems. RCBS dies, no expander-just inside chamfering of the case (done once), seated to 1.125" loa and then crimped with the Lee Bottle Neck Pistol factory crimp die.
Very good group size and the BN crimp is responsible for that.
More info (gun, dies, powder charge, cases, sizer die, lube) would help.

[Blammer]

tumble your cases before they are primed, I suspect (although you didn't say) that you still have some case lube in the neck and with the tad of air pressure it's forming a seal and pushing the boolits back out.

tumble them will clean out this lube.

I'd first worry about your keyholing. What kind of barrel rifling do you have?

[44man]

With proper dies I have never seen this either, sounds like the case is expanded too much.
This problem is common with a BPCR when the brass is not sized so the boolit can be seated by hand. Since the powder is compressed and there is usually a wad on top, there is no place for air to go so it will keep pushing the boolit up and I have to keep pushing them back down until the air is gone.
You might try just leaving the press handle down a while, holding the boolit, before you crimp. Maybe the air will escape. That is a very small case with no room for the air.

[mdi]

I can think of two thing off hand (but I'm no expert). The walls of the cases are tapered and maybe the larger bullets are being squeezed out by the taper. Or insuffecient neck tension from expanding case mouth too much? I also like the idea of too much lube on the bullet and/or the case.

[pt4u2nv]

That's pretty strange. Been loading for 40 yrs and haven't seen that or heard of it. I don't know what kind of "sizer" you're using, I suspect Lee push through if your finished sizes are off that much; unless it's your caliper or your reading of your caliper that is off.
I use the Kead 125 TC BB (sized .358) in my G32 and have no problems. RCBS dies, no expander-just inside chamfering of the case (done once), seated to 1.125" loa and then crimped with the Lee Bottle Neck Pistol factory crimp die.
Very good group size and the BN crimp is responsible for that.
More info (gun, dies, powder charge, cases, sizer die, lube) would help.

Shooting a SIG P238, RCBS sizing dies,standard RCBS expander plug in sizer die, 7.7 grs AA#5, Speer and Fed cases, RCBS case lube on cases ( tumbled after sizing ) and Bull shops green lube on boolits. All boolits after run thru sizer dies are being checked with a lyman micrometer, haven't had a chance to check that with another mic but I am still suspecting the move to the larger boolit is the culprit because I did not get this with the ones sized with the .357 sizer. I have also been loading for 30+ years and never saw or heard of this either.

[44man]

I have gotten desperate with my BPCR loads and stuck a dog hair alongside the boolit to vent air. :mrgreen:

[pt4u2nv]

I have gotten desperate with my BPCR loads and stuck a dog hair alongside the boolit to vent air. :mrgreen:

My dog would not appreciate me pulling all of his hair out to load up boolits .:twisted: