roll crimp or taper crimp

[ted]

I have a colt python and want to start reloading for it again. I will be doing some silhouette shooting with it. Is a roll crimp better or taper crimp?

[Robert357]

As to roll crimp or taper crimp, I think that the answer depends upon a few variables.
 
Traditionally a revolver uses a roll crimp, especially if you are using cast lead bullets.  That is what I use on many of my 357 mag and 45 Colt cast lead hand loads.  If you are shooting lead SWC or WC, for targets, I would expect you to be using a roll crimp.
 
Having said that, if you are shooting indoors in an environment that discourages "lead" and you are shooting Rainier copper coated lead bullets in your revolver, the Rainier website states very firmly that you should never use a roll crimp and only a modest taper crimp in their FAQ section!  Since a lot of target shooting is done indoors these days and since airborne lead is a "big deal" at indoor ranges, total jacketed bullets and taper crimps may be what you shoot use in those situations.  
 
If I were shooting heavy jacketed bullets in a revolver, I might opt for a taper crimp, depending upon the caliber.
 
Considering that there are also 9mm and 45 ACP revolvers out there, I don't think that you have given us quite enough information.  
 
Oh, there is also the Lee 4 die deluxe die set that includes their factory crimp die, which is a little different than a traditional roll die.  I kind of like that for hunting loads.  You might like that for your silloette (sp) shooting.  I have found that in my Ruger Blackhawk 357 with heavy Alliant 2400 powder loads and a 200 grain jacketed silloette (sp) bullet, I have to load it real long, which is were the Lee Factory Crimp really comes in handy! Heavy recoil loads with heavy bullets should usually have a strong crimp.

[New Hampshire]

The purpose of the crimp is to keep bullets from jumping under recoil, and to a slightly smaller degree in helping your burn.  Neck tension is what determines wether your loads sink or swim.  For the super slow powders, like 296, the roll crimp is usually required (there are exceptions of course.)  But for the most part a either crimp should do.
Brian M.
P.S.  The key to perfect crimps every time is trim length.  This is ESPECIALLY true fr roll crimps, but taper crimps benifit from uniform case lengths.

[ted]

Thanks for the info guys!. I will be using 125-158 grain jacketed bullets. Either Lil'gun,or 110 powders. It sounds like a taper crimp would be best for this situation if I am reading your posts correctly.

[KN]

No you have it backwards. If you are using H110 then you are loading pretty hot rounds. You want a roll crimp with that.  KN

[New Hampshire]

Sorry for any confusion.  But yes, you will want a roll crimp because H110 is one of those slow powders I mentioned (similar to 296) that needs the roll crimp.  Dont worry about no cannelure on the plated bullets.  You should be able to crimp into the plating because its actually pretty thin.  Lil' Gun, on the other hand, does not need a heavy crimp and the taper crip will do.  Same goes for the old standbys like 231, unique, bullseye etc, etc.  They are more energetic powders that do not require a heavy taper.
Brian M.

[ted]

Thanks  for setting me straight! I will be getting a roll crimp!

[Donna]

Just to throw a monkey wrench in the works. I use a taper crimp in my .30 cal M1 carbine both in the rifle and pistol with jacketed bullets using the 110 powders and have had great performance. The roll crimp will work the case mouth a bit more causing more work hardening of the brass leading to split or cracks in the case mouth area more than a taper crimp will do. The lee factory crimp is like a taper crimp on steroids but it is good I use it on my 45-70.

Donna

[Dave in WV]

Taper crimps are primarily for semi-autos and revolvers normally get a roll crimp. Most semi-auto pistols headspace on the case mouth so roll crimping will cause them to not headspace properly. The roll crimp holds the bullet more secure. You don't roll crimp a bullet that doesn't have a cannelure. Dave