First rounds

[rawhide]

Finished my first loads last night. Having a little trouble determining proper crimp.

Round on left is what I see as a light crimp and the round on right a medium/heavy crimp. My opinion of the crimps is based on reading and viewing pictures online only.

What do you guys think?

Chose these as my first loads. Screwed up the first few and decided to practice with unprimed, uncharged cases. that helped alot.

Tried to start as simple as possible. These are 38 sp, Winchester cases, WSP, 4 grains Unique, J/K 158 RNFP. RCBS IV and Lee dies.

Actually crimped as a separate stage because I am still having trouble setting the seater die to both seat and crimp properly.

 

[Shriner]

rawhide - you may need to spilt the difference bewteen the two .

 

[alank2]

Hi,

Sometimes how much crimp is a balancing act. If you have a powder that lights easily and doesn't need a firm crimp, you can go lighter. If you are shooting light loads that won't make other bullets jump their crimp in a revolver, you can go lighter. I'm not very familiar with lead bullets, but I'd probably crimp the case mouth into the lead just slightly. Heavier crimp will take its toll on a case mouth and limit the number of reloads you'll get before cracking...

Good luck,

Alan

 

[Woodcutter]

It looks like the case on the left has plenty of crimp. The one on the right appears to have too much. In fact, you may be able to get away with even less crimp that what you have on the left. Like Alank2 said, using the least crimp that will keep the bullet from moving will prolong the life of your brass. Four grains of Unique is a mild starting load, and Unique is a very easy power to ignite, so you should not need a heavy crimp. The powder should burn completely and the bullet should not jump forward in its chamber when another round is fired, so increase the life of your brass by using only a light crimp.

The type of firearm can also factor into the equation of how much crimp to use. If you are using it in a very light alloy snub-nose revolver such as a S&W Aluminum alloy Airlight, you will need to use a heavier crimp because the recoil acceleration of the firearm will be substantially greater than if you are using it in a heavy steel revolver such as a 6 or 7 inch long all-steel Ruger Blackhawk. To see if your crimp is adequate, load a few cases and put a light crimp on the bullets. Then measue the overall length of these loaded cartridges with a dial caliper and record their lengths. Then take them to the range and load a cylinder full. After each of your shots, remove the rest of the rounds in the cylinder and measure their lengths. If the unfired rounds are growing in length, stop shooting that batch of ammo and increase the crimp on them. Beware that if you screw a roll crimp die down too much, you will actaully bulge the brass wich will decreast the amout of holding power of the case, and also it could bulge to the point where the cartirdge will not load into the chamber.

Also, you will increase the life of your brass if you only bell the case just enough to seat the bullet without shaving lead.

 

[rawhide]

Thanks all. And Woodcutter I will mostly shoot them from a GP100 .357 but I also have an Airweight and would really like to develop a light practice load for it. I've loaded a little over 100 with about 1/2 of each crimp. I'll do the caliper test with each batch in both revolvers as well as the the few that were different cases. Most were Wincherster cases, but a few were S&B, R&P, and Speer. Guess I'll just have to shoot them

 

[NikatKimber]

I agree that the round on the left looks right for anything less than a full house magnum round.

 

[rawhide]

Just shot the whole batch. The lighter crimped rounds were more accurate. Recoil was very light. They were pretty dirty and I was surprised to see some unburned powder.

 

[alank2]

Hi,

Just shot the whole batch. The lighter crimped rounds were more accurate. Recoil was very light. They were pretty dirty and I was surprised to see some unburned powder.

Some powders don't burn cleanly at light pressures and this can result in dirty and/or unburned powder. Try some VV n320, it is my favorite all around light powder that burns clean even at low pressures. I've put in 38 special through 45/70...

Good luck,

Alan

 

[rawhide]

Just fired a second batch. Increased Unique to 4.2 grains and I think a much better crimp. Powder burned much cleaner and recoil still very, very light. I think I'm gonna like this new hobby.