max503
Member
A firm roll crimp will give more consistent powder burn. There's a chart in my Speer Manual but it is downstairs and I'm too lazy to go down and take a pic.
roll or taper crimp for 38/357
- Thread starter magnumb
- Start date
I only use a HEAVY crimp on my "FBI" Lswc full loads, that will be used for SD, only.
All other 38/357 bullets get a medium light to light crimp to the cases
depending if lead target or JHP practice loads.
Pistol ammo is all tapered, with no cripms, to the bullets.
twodog max
Member
I roll crimp all rimmed rounds. Just recently tried my hand at powder coating because I have come by several hundred pounds of pure lead, or close to pure, and had to find a way to shoot this. So far the powder coating has worked. I have been using it mostly in lever guns. I have not observed any breaking of the coating with a roll crimp in either 357 or 45/70 that I have loaded so far.
Back to the subject at hand you have to roll crimp for lever guns or the case mouth tends to hang up while chambering. Also several of my moulds throw bullets that are shaped so the crimp groove cannot be used or the bullets are to long to feed. Even in those I see no breaking of the powder coat
Back to the subject at hand you have to roll crimp for lever guns or the case mouth tends to hang up while chambering. Also several of my moulds throw bullets that are shaped so the crimp groove cannot be used or the bullets are to long to feed. Even in those I see no breaking of the powder coat
LoboGunLeather
US Veteran
I like the Lyman M-die very much and have one for just about everything I reload regularly. Very consistent results and minimum working of the case mouth for seating and crimping operations.
I have always followed the old rule of roll crimp for revolver, taper crimp for autoloaders and this is a good general rule. Cast bullets intended for revolver use will always have a suitable crimping groove. Cast and swaged lead bullets without crimp groove can usually take a moderate roll crimp, biting into the lead enough to secure the bullet.
Jacketed bullets without cannelure cannot take a roll crimp without damaging something (sometimes buckling or bulging the case), not a practice to be recommended.
My experience with plated and coated bullets is so minimal that I cannot comment usefully. Others will be able to help more, and consultation with the bullet maker could be helpful.
Major advantage of the taper crimp, in my opinion, is that the results are not as dependent upon exact case length uniformity. Generally any case that is within tolerances (minimum-maximum overall length) can be used satisfactorily.
Case length uniformity is more of a factor with the roll crimp to achieve consistent results. I start each batch of brass with trimming to minimum OAL and keep those batches together throughout their useful lives. The general theory is that consistency has positive effects on ignition, powder burn rates, and accuracy.
A final thought to keep in mind is that anything manufactured in large quantities will have variations in every dimension due to manufacturing tolerances. This applies to firearms, reloading dies, chambers, throats, bores, grooves, cartridge cases, bullets and everything else involved in this sport. There is no such thing as an absolute rule from one manufacturer to the next, or even within each production run (tool wear factors in). These variations are usually very small, within the accepted range of tolerances, but it is possible for tolerances to "stack" (i.e.: a combination of minimums or maximums in several pieces and parts). Even the base materials (steel alloys, brass alloys, lead alloys, etc) can cause minor variations, and all can change depending on ambient temperatures (smaller when cooler, larger when warmer).
Every combination will give different results, and every time any single component is changed there will be a need to start from the beginning all over again.
Probably the most difficult concept to absorb for new practicioners. Just because the SAAMI spec is 0.357" does not mean that every single item will be exactly 0.357"; one manufacturer's tolerance range might be 0.3562" to 0.3580", and another manufacturer's range might be 0.3555" to 0.3585". Most commercially available components, dies, and firearms will be pretty darn close, but occasionally we can find ourselves dealing with enough tolerance variations to make us a little crazy.
I have always followed the old rule of roll crimp for revolver, taper crimp for autoloaders and this is a good general rule. Cast bullets intended for revolver use will always have a suitable crimping groove. Cast and swaged lead bullets without crimp groove can usually take a moderate roll crimp, biting into the lead enough to secure the bullet.
Jacketed bullets without cannelure cannot take a roll crimp without damaging something (sometimes buckling or bulging the case), not a practice to be recommended.
My experience with plated and coated bullets is so minimal that I cannot comment usefully. Others will be able to help more, and consultation with the bullet maker could be helpful.
Major advantage of the taper crimp, in my opinion, is that the results are not as dependent upon exact case length uniformity. Generally any case that is within tolerances (minimum-maximum overall length) can be used satisfactorily.
Case length uniformity is more of a factor with the roll crimp to achieve consistent results. I start each batch of brass with trimming to minimum OAL and keep those batches together throughout their useful lives. The general theory is that consistency has positive effects on ignition, powder burn rates, and accuracy.
A final thought to keep in mind is that anything manufactured in large quantities will have variations in every dimension due to manufacturing tolerances. This applies to firearms, reloading dies, chambers, throats, bores, grooves, cartridge cases, bullets and everything else involved in this sport. There is no such thing as an absolute rule from one manufacturer to the next, or even within each production run (tool wear factors in). These variations are usually very small, within the accepted range of tolerances, but it is possible for tolerances to "stack" (i.e.: a combination of minimums or maximums in several pieces and parts). Even the base materials (steel alloys, brass alloys, lead alloys, etc) can cause minor variations, and all can change depending on ambient temperatures (smaller when cooler, larger when warmer).
Every combination will give different results, and every time any single component is changed there will be a need to start from the beginning all over again.
Probably the most difficult concept to absorb for new practicioners. Just because the SAAMI spec is 0.357" does not mean that every single item will be exactly 0.357"; one manufacturer's tolerance range might be 0.3562" to 0.3580", and another manufacturer's range might be 0.3555" to 0.3585". Most commercially available components, dies, and firearms will be pretty darn close, but occasionally we can find ourselves dealing with enough tolerance variations to make us a little crazy.
GypsmJim
Member
- Joined
- Oct 16, 2009
- Messages
- 4,078
- Reaction score
- 7,180
My 9 different handgun calibers are all reloaded with Lee Dies. All the dies seat and crimp at the same time. I have done it this way for 52 years. Lead boolits, jacketed, plated or coated - all the same. The only collet crimping dies I use are for rifle bullets, and only if the seating die does not crimp as well.
I think the biggest advantage of a separate crimping die is that you don't have to readjust the bullet seating stem when fiddling with the crimp. The crimping die is really nice with presses that have 5 stations.
Pig Hunter
Member
Some of the PPC shooters used the taper crimp on .38 spec. wadcutter target loads. Heavy guns and light loads eliminated the possibility of bullets moving forward. Try it both ways. If your loads work without bullets moving and you get the kind of accuracy you want fine. Light guns with heavy loads will have bullet pull and require a heavy roll crimp. Customizing loads and methods are what hand loading is about.
Taper crimp will work under most scenarios. Roll crimp will work under all scenarios. They make both because some people will buy both...
Under limited scenarios one might be preferred over the other. I don't ever use a taper crimp for revolver rounds. A light roll crimp is effectively the same thing.
Under limited scenarios one might be preferred over the other. I don't ever use a taper crimp for revolver rounds. A light roll crimp is effectively the same thing.
Last edited:
wow this is a great dialog! Since I will be using some of this ammo in a lever action, apparently roll crimp is better for feeding per several comments, including marlin owners forum. I also don't want crimp jump on high power loads in my model 19 2.5 inch. or 4 inch. I since learned that my lyman seating die can do a roll crimp. I will be starting with that since the missouri bullets I ordered all have grimp grooves. Thanks for all the experienced comments!
ArchAngelCD
Moderator, SWCA Member, Absent Comrade
I wouldn't use a taper crimp on any revolver load. You can apply a roll crimp to coated bullet without breaking through the coating. Just don't be an animal lol.
If you are a competitive shooter you are probably shooting an 8 shot revolver (but same applies to a 6 shot). Trying to do a quick reload with taper crimp rounds is very slow because the edges of the rounds catch the cylinder and you have to wiggle the moon clip or speed loader to get the rounds in. Unless you do major throating to the ejector and cylinder the rounds usually will not just drop into the cylinder like roll crimped rounds will.
Paul in Nevada
Member
- Joined
- Mar 30, 2021
- Messages
- 870
- Reaction score
- 1,019
Taper crimp is ideal for 38 wadcutters or bullets without a cannelure. Everything else should be roll crimped.
Even BBwc or HBwc bullet cases, can be crimped
since the crimp does not dig into the bullet, to cause any accuracy problems
as seen in this Remington factory loading and two reloads, of mine.
Good shooting.
GypsmJim
Member
- Joined
- Oct 16, 2009
- Messages
- 4,078
- Reaction score
- 7,180
Once a year I mine my personal sand trap to collect boolits for recycling. My roll crimped coated or plated non-cannelure bullets show no signs of breakage.
I agree that it's nice to be able to adjust the seating depth and crimp completely separately. However, I think the biggest advantage of crimping in a separate step is that the bullet isn't moving downward while the crimp is being applied. This is even more important if your bullet doesn't have a cannelure or crimping groove.
P.S. one of the reasons I like Redding's Profile Crimp dies so much is that it gets the job done with less sensitivity to case length. If a case is a touch short, at least it still gets a bit of taper crimp. If long, just a heavier roll crimp.
Last edited:
Thankful for this post and replies. It has been a number of years since I reloaded for my revolvers and my pistols. Local public range has now opened. Come next year, going to be put out to pasture, so hope to do some reloading/shooting before I move. This will be helpful. Sincerely. bruce.
