Crimping with RCBS rifle dies

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judaspriest

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Hi,

I have a new set of (two) RCBS 7.62X54R rifle dies. The manual seems to imply that there are two types of seating dies, with roll or taper crimp. Mine seems to be of the roll variety (no TP or any other special mark on it).

I followed the instructions and tried to get a crimp by adjusting the height of the crimp stem (screwing it deeper into the die), however instead of increasing (or even creating) crimp, it just seats the bullets deeper.

I was wondering if anyone has any experience with these dies and could share some tips.

Many thanks!

JP
 
judaspriest,

When setting up the die seat the bullet to your desired length. Then either remove seating plug or back it off so it can't come in contact with the bullet when you adjust the die down to crimp.
 
The manual has a lot of info not specific to the die you have at hand. Rifle dies will have a roll crimp. You can adjust the die for a light, heavy or no crimp at all. I use nothing but RCBS dies.
 
Good advice so far...

Judaspriest--I would only add an explanatory note: Roll crimps are for rimmed cases in handguns, and for bottleneck rifle cartridges, like yours. Taper crimps are for straight-walled, non-rimmed cases (e.g. .45ACP, or .30 Carbine) where the case headspaces on its mouth. Obviously if the mouth is the headspacer, we can't have it rolled down into a crimping groove.

Seating a bullet and crimping can be done in the same operation, by first adjusting the depth of the seated bullet, then backing off the seating stem and adjusting the crimp, then with the cartridge in the die, screwing the seating stem back down so that both the crimp ring in the die, and the seating stem, are the exact right height to both do their jobs correctly.

BTW, just a thought--Do you need to crimp these rounds? 7.62x54R's are usually used in a Mosin-Nagant, a bolt action rifle. Bolt rifles often function just fine with non-crimped ammo. Tubular-magazine rifles, and autoloaders usually need crimped ammo. If you don't have to crimp, that's one less piece of fussing to do.

Anyhow, hope you can get it to work for you. :)
 
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Mr. Smokey Joe,

Many thanks for the very useful info. Looks like I would use a roll crimp for all my reloads (7.62x54 as well as 38/357 revolver) as they are all rimmed. Makes total sense.

Of course you are also right, I don't need the crimp all that much for my MN M44 (wish I had an SVD which is an AK equivalent in 7.62x54!, but forget about it in my liberal state...). I still wanted to crimp them a bit just to be sure. My reasoning is that even though it's not a semi-auto, but I still have a pretty respectful recoil, so it's better to crimp slightly than not at all. I might be wrong of course.

Thanks again,

JP
 
It never ceases to amaze me when someone asks a specific question about a component/tool they have in hand, that someone will always tell that person to junk that tool for a "LEE COLLET, or FACTORY CRIMP" die.

People have been using RCBS, Lyman, Dillon, Forster, Redding, Lee and other, roll and taper crimp dies for some 70 or more years with great success.

I'll admit, I have a Star Lubrisizer, That I think is more efficient and easier to use than other brand/models. But I don't go around telling people to buy a Star when they've asked something about a Lyman or RCBS.

I guess it's sorta like someone telling me that an H2 is far superior than my PowerStroke Diesel pickup truck.

-Steve
 
Use the Lee Factory Crimp die, as already suggested. It is cheap, it makes an excellent crimp, and it very nearly duplicates the crimp found on factory ammo.
 
I followed the instructions and tried to get a crimp by adjusting the height of the crimp stem (screwing it deeper into the die), however instead of increasing (or even creating) crimp, it just seats the bullets deeper

1st you are adjusting the seating stem not the crimp.

The proper way to adjust the RCBS (also Redding, Lyman, Hornady, and others, roll or taper) is to place a case in the shell holder on the press ram raise it to the top of its travel, then screw the die body, minus the seating stem (the stem that screws in the top of the die body) into the press until you feel it make contact with the case mouth.

Re-insert the seating stem, and with a bullet in the case mouth adjust the seater down until the bullet is at the depth you want and lock the stem in place with the lock ring/nut.

Adjust the die body down in 1/16 turn or so increments deeper into the press checking the crimp as you go.

Stop and lock the die bodies lock ring/nut when you reach an exceptable crimp.

Recheck the COL and make any minute adjustments with the seating stem if needed.
 
You should be able to get away with no crimping at all. Neck tension is usually enough. Crimping is for heavy recoiling cartridges and ammo used in a lever action's tube mag.
You don't need to crimp a .38 either.
 
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