Comped .45 ACP questions

[Whistler]

Hello!

Not very active on this forum, but gathered you guys have expertice for this particular question.

If this thread is more suitable in the Revolver forum then any mod can feel free to move it, however my questions concern primarily compensators.

I am planning a project for an Open Revolver for use in PPC.

This is my first comped gun, so please bear with me with the technical details.

My plan is using a 5" Model 625 chambered in .45 ACP with the 200gn H&G 69 (plain based LSWC) using 10-11gn Vihtavuori N105 in a comp with three large cuts directing the gas straight upwards.

The comp is currently .430 and the previous owner used it with a .38 revolver (which is probaly why he sold it). My plan is to widen the comp to .468-.469" for use with .452" projectiles.

The first concern is accuracy. It has to be able to do at least 2" groups at 50 yards. The gun and bullet in question can do that presently, but with faster propellants like 5.1gn N320 or Bullseye. I am thinking that N105 will reduce recoil by working the comp, but how does compensators affect accuracy?

I will also be using an UltraDot red dot sight.

Am I on the right track?

Edited August 17, 2011 by Whistler

[Whistler]

A hundred views but no replies?

Well, I've started doing some testing.

My earlier loads of 5.1gn N320 with 200gn LSWC and 3.6gn BA10 with 230gn LRN both are very accurate. The loads with N105 were not, though I could feel (and hear!) how the comp was utilizing the extra gas flow. The N105 loads were way hotter than the other, but recoil was still manageable with a PF of ca 200. I will continue testing and try to find accuracy with the slower powders. 6.0-6.5gn N340 might be suitable for the 200gn LSWC.

Edited August 21, 2011 by Whistler

[superdude]

you're on the right track working with slower gunpowders. i can't feel much if any benefit using fast powders like 231 in my comped 45 auto compared side-by-side with my non-comped 45 auto. but using a slow powder like Longshot makes a world of difference since it produces lots of gas to run the compensator.

[L9X25]

We developed some loads with WAP and 152gr & 155gr projectiles that felt incredibly good. You will have to see how hard your barrel can push the light bullets while maintaing the accuracy that you demand. Unless you are wanting to do bowling pins, I would keep the velocity closer to the minimum that you need for the rules. Shooting 200PF+ is not good for a 625 and it will shoot a lot flatter and softer with the light projectiles and a lower factor. VV N-105 will work great too.

Edited August 22, 2011 by L9X25

[Whistler]

N105 gave me lots of unburned powder in the chambers and bore. I know from experience that the yellow crud will get in behind the extractor star and make the cylinder bind.

If I lessen the amount of powder I will get even more unburned powder left. Quickload says that my load of 11gn N105 had a burn rate of ca 75%. The one way to correct this would be to reduce the charge and then seat the bullet deeper to keep the pressure high enough and improve burn rate, but then the SWC shoulder is below the case. This might make it harder to reload, even with clips.

I believe you are right about the PF. Even though it works the comp, going with lower velocity will give me less recoil and more time for trigger squeezing. The Open division in PPC does not a PF requirement at all, the only rule is that the gun is safe.

Edited August 23, 2011 by Whistler

[Flexmoney]

I edited your topic title, maybe you will get some more/better info. Even though you aren't shooting pins with it... Talking 200pf comped revolvers just makes me think of pin guns.

- Admin.

[Bill Nesbitt]

Back when we were shooting 45 single stack comped guns, we ran faster powders like Bullseye and 231. That was at the old 175 power factor. They seemed to work the comps OK.

I've had pretty good luck with Bullseye running clean in my non-comped revolvers.

[stardust tommy]

since you are loading VV powder and vectan (ba10) I think you live in Europe... try some of the lead Drummen Accuracy bullets. they are available in 175 grain (and 200 and 230) and verry soft shooting and accurate with slower powders (N340)

http://www.mauricedrummen.nl/webshop/contents/nl/d80.html

gr T

[Whistler]

Thank you, Tommy. However, I cast all my bullets myself.

The Lee 452-228-R1 has proven to be the most accurate bullet so far.

The 200gn H&G #69 is a proven bullet for PPC and Bullseye, so I will do some more tests.

Bullseye powder does seem to be pretty decent in theory, I will work up some loads and try.

[calishootr]

my only experience with comped .45's coes from my early days with the single stack auto's back then I ran the H&G 68 damned near exclusively, and at the then 175ish PF, i ran WST, which for me, had a soft felt recoil while still burning enuffto work the comp effectively, butthen again this was in an auto, i have no idea what it would do in a comp'd revo...i still have some ofthe rounds i made backthen and shoot em in a standard 625, andthey are fiesty recoilwise, i've tried to get 155's to work, and yes to a point, they work, lighter, more gas pressure to work the comp, but less of a bearing surface(i was useing a shortened version ofthe H&G 68)

[oldtrooper]

I have an older comped .45 Springfield. It has a Clark barrel and a Gilmore Shroud. It was fitted by a competent gun smith and will shoot 2.0", sometimes a little tighter at 50 yards loaded with WST and using 185gr SWC Bear Creek bullets (molly coated).

[DougCarden]

Are you trying to get best accuracy or make a Power Factor number. For the Best accuracy try VV310 with a 185gr bullet starting at 4.0grains and see what shoots best in your gun. If you are trying for accuracy, forget trying to make the comp work with slower powder. We tried all that during the bowling pin era. The comps in the .45s work best with 175PF and up, Mine was flat at 215PF....

Good Luck,

DougC