Seating and Crimping on microband

[Mr. Farknocker]

I spent some time casting boolits for my .38 special this weekend and tried to reload some of them last night. While reloading, I ran into a question about crimping. The Lee Precision specifications that come with the reloading dies provides a minimum OAL for this round. When I seated the boolit to the minimum OAL, the last microband sits above the case mouth and a crimp is made on the shoulder of the microband. My question is would it be ok to seat and crimp the boolit such that one or more or the microbands sits above the case mouth and is it ok to crimp the case on the shoulder of the microband instead of the grove??

[ku4hx]

You failed to mention the specific boolit, but if it has a crimping groove, use it. It it doesn't, you can crimp it at one of the tumble lube grooves if that's what you have. A heavy crimp on a 38 Special is not needed and in fact on some of my loads I crimp very little and sometimes don't crimp at all.

Cartridge OALs are just guides. As long as your cartridge chambers and the cylinder spins free you should be fine. It's best to avoid very deeply seated boolits.

[Boolseye]

I assume you're working with the TL 158 grain SWC or RN. Not that important where you crimp with these bullets, as long as they chamber and shoot well. I always crimp on the top band of the TL 158 SWC, with all the microgrooves hidden.

[Mr. Farknocker]

You failed to mention the specific boolit, but if it has a crimping groove, use it.

Sorry, I posted my question while running off to work and didn't have time to look up the specific boolit. It is Lee Precision's TL358-158-SWC. I don't think it has a crimping grove per se, just microbands for tumble lubing.

http://leeprecision.com/bullet-casting/hand-gun-bullet-molds/bullet-mold-double-cavity/

[Mr. Farknocker]

I assume you're working with the TL 158 grain SWC or RN. Not that important where you crimp with these bullets, as long as they chamber and shoot well. I always crimp on the top band of the TL 158 SWC, with all the microgrooves hidden.

That's the one. If I use the top band, the OAL will be less than the specified minimum by Lee Precision. My concern is that if the OAL is less than what is specified, I may be creating a dangerous situation with internal pressure.

[H.Callahan]

If you are shooting them in a revolver, about the only OAL restriction on the .38 is to make sure they are less than the length of the cylinder (so that the cylinder can rotate). Remember, wadcutters are seated flush with the case mouth, so nudging the bullet a bit to hit a groove is not a problem. If you are using a lever action rifle, you might have some feeding problems with different OALs, but I would still think that if it is a minor adjustment to OAL to hit a groove, it still will probably not be a problem.


My concern is that if the OAL is less than what is specified, I may be creating a dangerous situation with internal pressure.

Always work up the loads with whatever OAL you are using, but a minor adjustment should not produce any problems. Even with a major change in length, you can still be safe by backing off your load 10% or so and building back up looking for pressure signs along the way.

[Boolseye]

As has been shared, those OAL restrictions are really just a guideline. Your care is well-founded, but in this situation I would worry more about a double charge than a few thousandths of OAL.

My question is would it be ok to seat and crimp the boolit such that one or more or the microbands sits above the case mouth and is it ok to crimp the case on the shoulder of the microband instead of the grove??

To directly answer your question: yes, that's all OK, as long as they chamber and aren't too long for the cylinder of your gun.