.45ACP barrel length?

[Bigfoot]

Didn't know that Pug. That explains why the long barreled 45ACP is louder than I expected. How much quieter would a 9mm 147 grain subsonic load be in the same length barrel?

Originally Posted by d-mon

If you can provide me with the following info, I would be glad to calculate the right twist for your bullet.
I would need:
1 the bullet diametre in inches
2 the total bullet lenght in inches
3 the nose lenght in inches
4 meplat diametre in inches
5 Nose shape (tangent, secant, conical)
6 the material of your bullet :jacketed or lead

This is for a flat base bullet, the program needs more info for a boattail.

ND

Now THAT'S a calculator that I can trust, very nice. My software can provide the length of most factory bullets, tell me the bullet and I'll post the length. The meplat, nose length and tangent I can't help with.

[Wrangler]

If the sks is .311 what does the difference of .012 for the .308 bullet do to mess up accuracy since the bore is for the larger diameter bullet?

[Bigfoot]

Even less .003"

Here's some loaded 220 gr subsonic 7.62x39, I don't know of a .311 220 gr bullet so I assume it's .308 diameter. http://www.ebr-inc.net/detail.asp?id=3

[Wrangler]

oops! Yep, oh well. Thnaks for the link.I may try some of it.

[pug]

First there is a good chance that the 1:10 twist isn't going to stabilize the 220-240 bullets so their accuracy sucks anyhow. Some claim with fairly good bores they get excellent accuracy with the 308s but I am sure that varies barrel to barrel. My bore is pretty worn so I go with 311s but I would start with 308s and check accuracy. More weights available and also its a lot easier to punch out a 308 squib than a 311 if it gets stuck in the barrel.

[pug]

Bigfoot I forgot to mention the 147 grn 9mm with 3.8grns powder clocks around 980 fps out of a 16" barrel and sounds like a stndard velocity 22lr. With the extra 10" of barrel to cool and expand the gasses Im sure its quieter but dont know how much. Also you would need a 1:10 twist barrel (not some of the 1:16 floating around) to stabilize a 147grn bullet at subsonic velocity. Don't know if you even care but 147s and higher will cycle a semi or FA action also.

[Wrangler]

What powder and charge do you use with the sks and the 9mm?

[d-mon]

Hello Murmur,
unfortunatly I had to move to New zealnad and never had the chance to shoot my 300 whisper that I left in Scotland. So I could not compare it with the 44mag.
However , I used to shoot a 30-30 contender with subsonic loads and a silencer, the noise or the 44 mag with subsonic bullets and a sopson supressor was barely louder. I was extremely satisfied from this point.
I do not really know what affected the accuracy, weather a bad barrel or a supressor not properly mounted? I would blame the barrel first, because the silencer is cnc built and the guys who make it know how to fit them.

The ruger was properly bedded as well.

I think investing in a good custom barrel with the right twist is a key to accuracy.

ND.

[Murmur]

Hey everyone,
Well I've made up my mind to get a 17 1/2" (Our shortest legal length)
45ACP barrel for my Contender Carbine. JD of SSK Industries recommended the 45ACP route with a 1-16" twist barrel over the 44 mag or 45 colt for subsonic use. Reportedly they have excellent accuracy and ammunition such as Winchester Ranger, Federal Hydrashock & the Speer Gold Dot apparently expand well on deer at 75yds. The 45 should fit the bill nicely as I intend to use a suppressor.....and factory ammuntion is already subsonic!
JD has been extremely helpfull on the matter - I'll keep you posted with the results when I get my barrel in a few months time.

[Greywuuf]

I finally found this message thread and thought I would add what little I can.
First off the making 45 acp brass from 308 is NOT easy well ok it isn't hard but it sure sucks, a considerable amount of case wall must be removed either by inside reaming or outside turning. secondly, I see it sorta mentioned, but lets not forget that there are at least two standard 45's out there, the pistol with bullets in the .451-.452 range ( some older guns were actually .454) and the rifle which is normally .457-.458.

and last I have a 21" winchester '94 in .45 Colt ( long colt if you prefer) and I regularly shoot my heavy revolver loads in it and I would not consider it even remotely quiet. granted I am pushing 300 grain cast slugs over a pretty healthy dose of H110, and it chrono's substancially faster out of the long tube ( several hundred feet faster... in the 15-1600 fps range) as compared to 1100 in a revolver (from memory and generalized I didn't dig out my chrono log and look)

interesting concept though... I might have to dig up some unique loads and see how it sounds about seven grains is a decent compromise in the LC case with 230 grain ball bullets (cheap too as it works out as an even 1000 rounds per pound of powder) if memory serves thats about a 900 fps load in the revolver.

gotta go get ready for winter
Dan in Alaska