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Thoughts on Crimping Revolver reloads

#1 Rimmed case Revolver reloads. Most Revolvers shoot rimmed cartridges. The recoil tends to act like an inertia bullet puller. The cartridges in the cylinder may let the bullet move forward in the case. This can keep the cylinder from turning. So a crimp may be called for. Bullets may or may not have a crimping groove.

If a bullet does not have a crimping groove then adjust the seater plug on the seater die for the O.A.L. of the loaded cartridge with the die turned far enough out to impart no crimp. Now back out the seater plug. Start the die body in 1/4 turn at a time until you get a small amount of crimp. Too much crimp will budge the case Not Good. If the bullet has a Crimping groove start the seater plug with the die body turned out far enough to impart NO crimp and then adjust the seater plug so the crimp groove is lined up with the mouth of the case.

Now turn the seater plug out and the die body down until you get the proper crimp. Remember that if you try to seat and crimp in one operation the bullet will be moving farther into the cartridge as you are crimping NOT GOOD. I like to adjust the seater plug with the die turned out 1/2 of a turn from any crimping then turn the plug out one full turn and turn the die body in 1/2 turn for proper crimp. Trouble Happens when trying to apply TOO MUCH crimp or crimping and seating at the same time.


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    gunnut505gunnut505 Member Posts: 10,290
    edited November -1
    I concur.
    That's why my Dillon 550 has a separate station for crimp after the seating stage.
    Now we need to explain the difference between roll crimp and taper crimp, and on which rounds either is acceptable.
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    gregoryhart1gregoryhart1 Member Posts: 518 ✭✭✭
    edited November -1
    I recently started to seperate my seat/crimp step. I don't do this on low power target loads but as I develop hotter loads for my .357 I want to have a higher level of consistancy in my loads.
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    flapjackflapjack Member Posts: 58 ✭✭
    edited November -1
    If you use a Lee carbide factory crimp die, it will produce a more consistant bullet, and is almost idiot proof to use. It is a separate step in the loading process.
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    v35v35 Member Posts: 12,710 ✭✭✭
    edited November -1
    A heavy crimp is essential in thin walled brass using heavy bullets like 45LC, 44-40, 38-40 & 32-20.
    Also, as carry pistols and revolvers get lighter, the inertial effect
    on ammunition becomes greater for bullet movement, making good crimping important.
    The 9mm with its' relatively thick brass does manage to get away with no crimp.
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    jade30jade30 Member Posts: 3 ✭✭
    edited November -1
    I recently started to seperate my seat/crimp step jade.I don't do this on low power target loads but as I develop hotter loads for my .357 I want to have a higher level of consistancy in my loads.
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    woodshed87woodshed87 Member Posts: 25,785
    edited November -1
    I Detect Plegurisum here[;)]
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    gotstolefromgotstolefrom Member Posts: 1,479 ✭✭✭✭✭
    edited November -1
    I agree with Perry.....mostly.

    On my 44 Mag loads -
    I will seat & crimp in one step ONLY in specific situations...
    Jacketed bullets with a good cannelure.

    As Perry said, the bullet DOES move during the seat & crimp operation...but restrict movement so you DON'T EXCEED THE CANNELURE's width or depth for this to be successful.

    A Sierra 240gr FMJ has a generous cannelure and can be seated and crimped in one step after adjustment to assure you don't let the case be pressed against the bottom of the cannelure..which can bulge/buckle the case and it will not chamber.

    In the specific conditions above, the crimp will just enter the cannelure...and THATS ALL YOU NEED. I've had consistent performance with this operation, which is particulary usefull with compressed loads. I've never checked, but I suppose the bullet could move to the edge of the cannelure...but that's all.I guess I will do that now and report my findings.

    For bullets that have no cannelure , a taper crimp die is common as a final step after seating. Which could be your operation all the time, and not fiddle with the adjustment of the seat & crimp die that I discussed, or the seat then crimp as Perry described.

    ENJOY !
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    Smitty500magSmitty500mag Member Posts: 13,603 ✭✭✭✭
    edited November -1
    A Lee factory crimp die works great. I use bullets for the .50AE that has no cannelure for my 500 Mag rounds and the factory crimp die will make it's own cannelure. I've never had a 500 Mag bullet back out of a casing using these bullets and there's not many calibers that have more recoil than a 500 Mag.

    I have had a bullet from factory ammo back out of a .357 Mag round that was shot in my S&W 340PD snubby that locked the cylinder up. But that gun only weighs 11.5 ounces and it's got a lot of recoil. I've never had a bullet back out of my .357 Mag rounds that I used the factory crimp die on.
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