Bullet Seating

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coachman48

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Hey

I finally got my reloading equipment,bench setup. I am using RCBS dies and Rockchucker press. I am loading 40S&W with Remington 155JHP. I have the oal at 1.135 - 1.129 and when I push on the bullet after they are crimped against the bench by hand it does not move back into the case any, but when I dry cycle thru my gun they get shorter. The aol will be 1.31 -1.124. Is this normal or do I need more crimp. I am trying to get my dies set up. I do not have not put any primers or powder in the bullets yet. Dumby loads :D

Thanks
Bob
 
You do not need more crimp. You need more neck tension. More crimp will not fix it. The case headspaces on the case mouth so you don't want to overcrimp anyway.

Perhaps your sizer is not tight enough (probably OK though. You may want to polish down your expander, or perhaps you are running it down in the case too far.

Check a sized case and see if you can run the expander plug into it without effort. If you can, your sizer is to big. If you can not, you can polish it down and get better neck tension that way. Then crimp normally with a light taper crimp.

Your O.A.L. is OK, as long as it feeds in your gun. I was loading 155 Gr TrFP's at 1.125 for mine.

By the way. What crimp die are you using?
 
Walkalong

The expander die does go into the case easy, but I just belled or expanded enough so the bullet would start in the case and stay there turned upside down. The die is a RCBS carbide seat and taper crimp.

I only cycled thru the gun to see if they would eject ok, maybe I should not have measured after that. I might try some factory ammo and see if the aol changes after 2-3 cycles. While I was loading they went in the barrel easy and came out easy.
Thanks
Bob
 
Walkalong

I went and tried some factory ammo, wally world winchester white box 165 grain and after about 2-3 cycles thru gun some of the bullets oal length changed about .002 or .003. they went from 1.116 to 1.114. Is this normal?? I would like to get this right before I install the primers and powder if not I will just shoot Blanks :D

Thanks
Bob
 
If it's only .002 or .003 it will not hurt a thing. Watch out for ammo that has been chambered repeatedly though. It may get too short. That is always a concern with reloads or factory ammo.
but I just belled or expanded enough so the bullet would start in the case and stay there turned upside down.
Click to expand...
I did not fully understand this.
 
Depending on the base of the bullet, i.e. if it has nice rounded edges, you might be able to get it into the case without flaring the case mouth. You might try running a dozen rounds through the sizing die, then skip the mouth die altogether, then when you seat the bullets, just make sure you go slow and easy. You're not going to get any more neck tension that that. Just be careful and go so to make sure that the bullet starts in the case and doesn't try to bind up on the mouth. A good chamfer will help. Just a suggestion. Good luck. I'd also put more crimp on it, but that's just me. That's the purpose of the crimp. To keep the bullet from moving forward or backward. The intertia of the bullet when the slide forces the round into battery is causing the bullet to move out.
 
Walkalong

Some of my reloading books or could have been the RCBS papers said to just expand the case just enough for the bullet to stay in the case when turned upside down. I did this prior to running into the seat crimp die. I probably confused you with my choice of words. :confused:

Thanks again
Bob
 
The case needs just a tad of flair most times. Any more will hurt potential neck tension. Crimp on auto cartridges is to get rid of the flair. If overdone it can mess up headspace. Besides, neck tension does 95% plus of holding the bullet put in an auto cartridge. No amount of crimp can make up for bad neck tension. It can only help when you already have good neck tension.
 
Strongbad

Is there such a thing as too much crimp if you are not deforming the case or the bullet ?

Thanks for the info
Bob
 
Walkalong

So I need to just expand the case enough so the bullet will just start in the case. I do not understand this headspace you refer to.

Bob
 
O.A.L. has nothing to do with headspace. As long as your chamber is OK, and I am sure it is, and your cases are in spec, and I am sure their fine, then you are OK.

Normally the case mouth will hit the end of the chamber and stop. That controls headspace in straight auto cases. If you taper crimp so much that the case mouth is too narrow and lets the case go farther into the chamber then it can artificially cause excessive headspace when mechanically everything is fine.

Rimless bottlenecked rifle rounds, like the 30.06, headspace off a point on the shoulder. Rifle rounds with a rim, like the 30.30, headspace off the rim.

Straight walled, or slightly tapered, rimless auto pistol rounds headspace off the case mouth. Rimmed pistol calibers, like the .38 Spl, headspace off the rim.

Headspace, very loosely defined, is the slop, or extra space (front to back) in the chamber when a round is chambered. There has to be a little slack so the round will chamber, but too much slack can cause all kinds of problems.
 
If you crimp correctly and your OAL is within SAAMI specifications you shouldn't have a problem with headspacing. This assumes you're loading for straight wall cases like the 40s&w.
 
This has always been a problem...We cannot see what you are doing and it makes it hard to picture what is going on in your reloading process. However those above, Walkalong and Otto, have given you good advice. Don't bell the case mouth anymore then what it takes to start the bullet. I've never heard or read that the bell should be enough to hold the bullet when held upside down. This seems to be a bit extreme for belling. When you crimp. Just remove any remaining bell. If you belled the case correctly you should or may not even have any bell left. For years I never removed the bell on my .45 ACP rounds because there wasn't any bell to remove. You might try that and not crimp at all.

Measure a factory round at the mouth and try to get the same measurment on your rounds. I bet if you bell the case mouth just enough to start the bullet you will find that the case mouth is the same as the facory round (without crimping) or +/- .001"...Try it and see.
 
Bushmaster

Thanks for the info. I tried some factory ammo and cycled thru the firearm and it has the same problem as my reloads, that being they get shorter the more they are cycled. So now I am thinking maybe you can not crimp or have enough neck tension to keep the bullet from moving. Maybe I should not have checked this and I would not be concerned about it. I did push the seated and taper crimped bullet against the bench by hand and it did not move any so thought this was enough.

Thanks
Bob
 
Bob...My carry ammunition, if I cycle it a few times, will shorten about .002 to .004" and I have never worried that much about it. However I have gone to using cases that have a cannelure around the case at the point where the base of the bullet will contact it to [help] prevent bullet set back.

As far as you running into this problem and posting it here. Good deal. Others that are new to this forum will get the advantage of this discussion and learn. Semi-autos tend to set the bullet back no matter how much bullet tention there is (not all of them, but most).
 
My 1911's shorten factory Hornady 230gr TAP by .002-.003", and my reloads by .003-.005. I don't worry about it, as that much (or little) shouldn't make a difference... But I duly noted the slightly larger change in my loads, and won't be exploring the outer edge of the loading envelope with them.

FWIW, I have Hornady dies, only bell very slightly (such that there actually isn't a bell after seating the bullet), and I taper crimp to .470".
 
LOL, yeah, I guess I took for granted that everyone would know case widths for 45ACP by heart :D

Sometimes I forget that there are other calibers out there!

Back to your regularly scheduled program... :eek:

Of course, my point was simply that "it happens"
 
I guess it could be possible for the bullet to actually go to the level of the powder charge if cycled enough. :confused:

Thanks guys for the info

Bob
 
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