I loaded my .357s with RMR .358gr plated match bullets today. I mic'd several of them and found them to be right on .358" consistently. They were all dead on. As far as outward appearance they look like any other plated bullet.
I'm hand loading on a Rockchucker Supreme single stage press with RCBS carbide dies.
I'm using maximum loads from Lyman's 49th edition.
Brass is my old winchester brass from 20years ago. I decided to use it to simulate standard, normal reloads.
I'm shooting a Ruger GP100 at 7yds. I don't have targets to show because I forgot my smart phone and didn't bring the targets home. You didn't miss anything.
I pressed a bullet in one empty case to set up the crimp as I wanted to see how hard it was to crimp these. Felt pretty normal even though I was crimping into the bullet with no cannular.
Then I knock the bullet back out to see if the plating was cut. It wasn't
It actually looked pretty good. I had visions of smashing the mouth of the from these being to hard. No problem.
Then I started loading them, my first load was 14.9 gr of 2400 seated to 1.608. I loaded 6 and checked them all and they were all within .002" of each other for OAL. The harder core doesn't deform like the softer plated bullets I've used.
#1= 1.609
#2= 1.608
#3= 1.607
#4= 1.607
#5= 1.6075
#6= 1.609 very good!
These had a pretty decent roll crimp.
Biting into the bullet didn't seem to cause any problems with bulging at the case mouth, they all fell in and out of my case gauge. I marked them with a sharpy pen 1-6 c
Then I loaded 6 with 14.9 gr of 2400 with no crimp, just straightened out what little flare there was. I changed the OAL by just raising the entire die up a half a turn or so.
#1= 1.614
#2= 1.614
#3= 1.614
#4= 1.612
#5= 1.6135
#6= 1.612
Then I did the same thing with the max load of Bluedot of 10gr and no crimp.
#1= 1.6125
#2= 1.6125
#3= 1.613
#4= 1.613
#5= 1.614
#6= 1.613
Off to the range.
The first 6 I shot were the crimped rounds of 2400. They shot as normal as my XTP loads shoot as far as recoil, horrendous muzzle flash and so on.
When I got to #6 I pulled it from the cylinder and mic'd it again.
#6= 1.617, after 5 of these it only moved .008". This looks pretty promising, I need to crimp a little harder.
Accuracy was pretty good but I wasn't shooting for accuracy. Around a 2"group at 7yd.
I then shot the uncrimped 2400 loads and the first thing I notice with the first five shots was that my group opened up to about 6" and I had unburnt powder all over the bench. Not enough tension on the bullet without crimping. Around a 6"group at 7yds.
The #6 bullet slipped forward to 1.635" slipping .023" certainly not enough to cause any problems cycling the revolver but it did slip without a crimp. The unburnt powder and 6"group though is a sign of inconsistent pressure with 2400.
Then I shot the maximum Bluedot loads with no crimp and they shot like the crimped 2400 loads, (with less recoil of course) they shot very accurately and my group size was about 2"again.
#6 bullet move out to 1.634 for a set forward of .022".
Even with this very brief amount of testing they definitely need crimped with the slower pressure building powder from what I saw.
#6 2400 14.9gr uncrimped = .023 slip forward
#6 bluedot, 10gr uncrimped = .022 slip forward
#6 2400, 14.9 gr crimped = .008 slip forward
I do like the idea of being able to just crimp into these with 2400 and not having hardly any more set forward than my XTP loads do.
I'll be doing some accuracy testing with these later at 25yds next time around, I want to load more with a little heavier crimp.