9mm 147 gr fn shaving lead

[Goober5263]

First post here and thanks in advance for the input. Relatively new to CB's with a new RCBS 9mm 147 grain fn (.356). Loaded with AA No.7@5.5 gr, and seated flush to the last lands an am getting some shaving and build up at the bullet seat in the barrel. Hesitant to seat deeper because I can start to see pressure signs on the primer. Anyone else use this combo and have similar issues or have any suggestions?

[Half Dog]

I size mine to .358” but for that to chamber I sent the barrel to DougGuy. I use a different powder so I can’t help there but it sounds like I seat mine longer. I’m sure others will chime in shortly with great advice. I find the members very helpful.

[Soundguy]

Is it shaving at seating and leaving a ring of crushed lead at the case mouth that then gets deposited at the chamber?

[Goober5263]

Yes it is. I have tried seating the bullet slightly deeper, knowing that will increase pressure but don't see any way other way to keep that from happening.

[Bird]

Changing the seating depth will not stop it from leaving a ring of lead when the round is fired.
Your boolits diameter is too big for your chamber throat. What is the sized diameter of your boolits?
What is the firearm?

[Soundguy]

Try flairing the case mouth more so it doesn't shave..then taper crimp..see if it chamber correctly then. If you gave a Lee FCD even better..it has a carbide ring that should iron out any bulges.

[405grain]

Welcome to the site Goober

When seating any cast bullet it is advantageous to slightly bell the case mouth. When I'm using new brass for the first time (both rifle and pistol) I take a chamfering tool and lightly break any sharp edges both inside and outside the case mouth. You only ever need to do this once, unless you later run the cases through a case trimmer, in which you'll need to de-burr the case mouths again. Prior to seating a cast bullet you should lightly bell the case mouth to prevent shaving lead. For most cartridges I use a Lee universal case mouth expander, but for 22 Hornet I use a Lyman M die. The bell on the case mouth doesn't need to be very big; I only bell the case mouths enough that half the height of the gas check will enter the case. With the case mouths belled and de-burred the (properly sized) bullets should seat without shaving any lead.

There is a second place in the bullet seating where lead can get shaved, and that's while crimping. I always use my seating dies with the die body turned out about 2 turns when seating the bullets. This insures that the bullets are seated to the correct depth without crimping the case. Then, after all the bullets are seated I back out the seating stem all the way and rotate the die body down enough to set the crimp. Cartridges like 9mm and 45 acp headspace off the case mouth, so you would not want a crimp, but the die body will still need to be lowered enough to remove the case mouth bell. Reloading dies are designed for use with jacketed bullets, and if you do the seating and crimping as one operation with cast bullets the mouth of the case can dig into the sides of the bullet as it's still being seated into the case, causing it to shave off a ring of lead.

On cast loads I always do my seating and crimping as two separate operations. The cast bullets should be (usually) .001" or so above the barrels groove diameter for best performance. When I'm reloading 44 magnum the internal dimensions on the RCBS seating & crimping die are so tight that it removes the case mouth bell before the bullet even starts seating, and would shave lead every time. Because of this I seat the 44 mag bullets using a 45 Colt seating die, then crimp the cases with the 44 mag die. The message here is to bell the case mouths slightly so that the bullets will enter the case without shaving lead, then do the seating and crimping as two separate operations so that the case mouth won't dig into the sides of the bullet.

[Bird]

Are you getting lead shaving when seating the round in the chamber, or when seating the boolit into the cartridge case?

[Soundguy]

Seeing many discussions on this form I'm sure it is highly confusing to new Reloaders to hear a lot of seasoned Reloaders say not to crimp something just to close the mouth flare when in fact for most semi auto cartridges that headspace on the case mouth it is correctly called a taper crimp and all of the major manufacturers call it this to say that there was no crimp is going to confuse a lot of new Reloaders that read their manual and see the word taper crimp and then wonder why people aren't doing it. Just an observation

[littlejack]

What Soundguy and 405 said.

[Goober5263]

Sized to .356 and the firearm is a Taurus G2c.

[Goober5263]

Welcome to the site Goober

When seating any cast bullet it is advantageous to slightly bell the case mouth. When I'm using new brass for the first time (both rifle and pistol) I take a chamfering tool and lightly break any sharp edges both inside and outside the case mouth. You only ever need to do this once, unless you later run the cases through a case trimmer, in which you'll need to de-burr the case mouths again. Prior to seating a cast bullet you should lightly bell the case mouth to prevent shaving lead. For most cartridges I use a Lee universal case mouth expander, but for 22 Hornet I use a Lyman M die. The bell on the case mouth doesn't need to be very big; I only bell the case mouths enough that half the height of the gas check will enter the case. With the case mouths belled and de-burred the (properly sized) bullets should seat without shaving any lead.

There is a second place in the bullet seating where lead can get shaved, and that's while crimping. I always use my seating dies with the die body turned out about 2 turns when seating the bullets. This insures that the bullets are seated to the correct depth without crimping the case. Then, after all the bullets are seated I back out the seating stem all the way and rotate the die body down enough to set the crimp. Cartridges like 9mm and 45 acp headspace off the case mouth, so you would not want a crimp, but the die body will still need to be lowered enough to remove the case mouth bell. Reloading dies are designed for use with jacketed bullets, and if you do the seating and crimping as one operation with cast bullets the mouth of the case can dig into the sides of the bullet as it's still being seated into the case, causing it to shave off a ring of lead.

On cast loads I always do my seating and crimping as two separate operations. The cast bullets should be (usually) .001" or so above the barrels groove diameter for best performance. When I'm reloading 44 magnum the internal dimensions on the RCBS seating & crimping die are so tight that it removes the case mouth bell before the bullet even starts seating, and would shave lead every time. Because of this I seat the 44 mag bullets using a 45 Colt seating die, then crimp the cases with the 44 mag die. The message here is to bell the case mouths slightly so that the bullets will enter the case without shaving lead, then do the seating and crimping as two separate operations so that the case mouth won't dig into the sides of the bullet.

Thanks again...I guess that I did not state that I am flaring the case mouth prior to seating, but you do make a good point that maybe I am getting some "shaving" when I both seat and taper crimp simultaneously. I am going to try and do those is separate steps. I like your step to use a separate seating die (your ....45), then crimp with the .44 die. Saves adjusting the same die.

[Goober5263]

Really good question. I don't think I'm getting the "shaving" when seating or crimping, but if I leave the boolit out at suggested OAL, then part of the shoulder is protruding from the case mouth and I felt like it was getting trimmed/shaved off when seating in the chamber. Hence I was attempting to get the full shoulder flush or slightly rebated at the case mouth to keep it clean when chambering, but that was making the load seem somewhat overpressure by having the boolit so deep. Now, with all these good comments I am wondering if I am creating this extra ring of lead by seating/crimping at the same time?

[Soundguy]

Bottom line.. If the bullet is still being seated after the case encounters the roll crimp shoulder..or the taper restriction on a taper crimp...it will shave. Ideally..the bullet stops moving right at the instant the case is crimped. Easiest way to see this is to screw die out far..and seat plug all the way down.. Adjust die body down in small increments till the bullet is where you want it. Now..screw seater all the way out.. Raise ram fully. Screw die in till it hits resistance..ie..the crimp shoulder or restrictions hits the case mouth..drop the ram a hair and then screw the die in 1/4 turn and raise ram..then check crimp..once you have it how you want it..raise ram to lock the die..and then spin the lock ring on the die to fix it's position. Next..screw seater in till it makes hard contact with the bullet...you should be set in a way that seats and crimps with minimal to no shaving. Keep in mind..on cast lead..it takes very little crimp on taper crimp rounds to hold them..as that case mouth leans into the lead easily.. Many times that first 1/4 turn crimp adjustment is plenty for semi autos..meaning there is virtually no vertical movement with the bullet as it gets the brass case mouth squeezed.

[405grain]

Lots of good advise here, and several things to look at to see what's causing the problem. Goober, if your reloads don't have the lead shaved on them, then your reloading technique is probably OK. If you are getting deformed lead and the bullet pushed back into the case when the round chambers, that means there's probably something amiss with the bullet design. First things first: if the bullet is getting pushed back inside the case, or if you're seating the bullet deeper, that will definitely increase the pressure.

From what you are describing the shoulder on that particular type of bullet might not allow it to fully chamber, and then when the slide/bolt closes it's getting mashed. The way to test for this is called a "plunk test". Open the mechanism on your firearm. In a safe place, with the magazine removed, and with the firearm pointing in a safe direction, and with all your fingers away from the trigger, slide release, etc., point the gun down and drop a cartridge into the chamber. Does it go all the way into the chamber, or does it get hung up and stop short? If the cartridge chambers completely then the dimensions on the cartridge are not the problem. If the cartridge gets stuck before it fully chambers it means that there's an interference somewhere. If the shoulder on your bullet is whats causing the problem it might mean that you should try a different style of bullet mold. If your still having problems post some more information and folks are likely to come up with a few solutions to try.

[trapper9260]

Lots of good advise here, and several things to look at to see what's causing the problem. Goober, if your reloads don't have the lead shaved on them, then your reloading technique is probably OK. If you are getting deformed lead and the bullet pushed back into the case when the round chambers, that means there's probably something amiss with the bullet design. First things first: if the bullet is getting pushed back inside the case, or if you're seating the bullet deeper, that will definitely increase the pressure.

From what you are describing the shoulder on that particular type of bullet might not allow it to fully chamber, and then when the slide/bolt closes it's getting mashed. The way to test for this is called a "plunk test". Open the mechanism on your firearm. In a safe place, with the magazine removed, and with the firearm pointing in a safe direction, and with all your fingers away from the trigger, slide release, etc., point the gun down and drop a cartridge into the chamber. Does it go all the way into the chamber, or does it get hung up and stop short? If the cartridge chambers completely then the dimensions on the cartridge are not the problem. If the cartridge gets stuck before it fully chambers it means that there's an interference somewhere. If the shoulder on your bullet is whats causing the problem it might mean that you should try a different style of bullet mold. If your still having problems post some more information and folks are likely to come up with a few solutions to try.

Good advice . it is best to do it with a dummy round to test this to keep it safe.

[Bird]

I think 405grain has the answer.
Make up a dummy round with your 356'' bullet and plunk test it several times. Check for shavings. I doubt you will see any. Next try plunking a 357'' then a 358'' bullet. Use the largest bullet diameter that will chamber. Then try cycling the dummy round through the action into the chamber a few times. It sounds like you have a semi wadcutter type bullet and as the boolit/round, travels up the feed ramp, the wadcutter shoulder is catching on the chamber mouth causing the shavings.
You can try and seat the boolit shoulder deeper/flush with the case mouth and see if it will chamber without shaving, but that will probably cause another problem. You would have to expand the case further down to accept the bullet at the greater seating depth to prevent sizing down of the bullet base which would cause leading of the barrel.
You want to have the internal diameter of the case sized no more than 0.002'' smaller than the bullet to prevent sizing down of the bullet. This may cause the round not to chamber. The only option you would then have is another style of bullet. Maybe a 125g 2r design, which I use without problems in a tight chamber.

[243winxb]

M type expander for better seating. Comes with RCBS die set.

Measure barrel throat diameter. Tap a oversize, as cast bullet, into the throat of the barrel. Remove & measure. Size bullets .0005" smaller.

Check diameter after sizing, before powder coat. Spring back/diameter changes with alloy used. Harder = larger.

https://www.thehighroad.org/index.ph...9mm-luger.317/

My bullets have to be smaller then .3568" to chamber.

[fredj338]

An adequate flare & separate crimping & seating should solve the problem of lead shaving. A expander like the Lyman M or sim is helpful.

[gloob]

More usually, when the bullet engraves into the leade, the bullet locks in place and won't come back out without a fight. If they shave lead when chambering, but they don't seize and lock in there? I suspect your G3C barrel has 2 things going on.

The leade is very sharp/abrupt, and the freebore is a bit generous to allow enough room for the shavings without locking up the bullet.

You can probably try a larger size bullet, say 357 or 358 to fill up the freebore a little better. But to avoid cutting into the leade, you probably want to try new bullet/mold that is shorter. Because my crystal ball says you don't want to pay a smith to extend your freebore and/or taper the leade, since you bought a G3C and want to reload lead bullets.

If you want to do some shadetree smithing, there are a variety of ways to taper a sharp leade. That might buy you a little bit of OAL. But you won't be able to increase the freebore by much, short of using proper reamer.