.45ACP barrel length?
 

How long would a .45ACP barrel have to be to quiet it down?

I've found out that a 26" barrel(I have one on the way) will quiet down a 22LR. The 45ACP has almost the same bore-case capacity ratio as the 22LR so I've got a hunch that a 26" 45ACP would be similar.

I'm thinking a Marlin Camp 45 with a longer barrel or one of the 45ACP Mauser conversions would be a perfect backyard gun that won't upset the neighbors if I drop a yote after dark. I had one sitting under a tree shaking off the rain for a full 5 min maybe 50' away from me a while back, he didn't know I was pointing a SKS at him almost the whole time. If I had the gun that I'm thinking about I could have dropped him without worrying that the new subdivision they built almost next door would call the county on me.

I have one of the Marlin Camp 45s. I don't know what barrel length it is. First, let me say that I wear a pair of the Tac 6s religiously. I want to retain my hearing!

When I pulled the trigger on the Marlin for the first time, I thought that the bullet must have been a dud, so I started checking for a stuck round in the bore. Not so. Another shot, same result. It was quieter than my 10/22. I took my hearing protection off and it didn't hurt AT ALL. It was VERY comfortable and very entertaining. It seemed strange that this thing didn't make any more noise than it did.

I don't know what you have in mind, but this gun is fun to shoot. This barrel length works, too. Keep in mind that if you reload, you have some control over how much noise any length barrel would make.

Jerry

Could you measure the barrel? Just put a small wood dowel down the barrel and mark it to measure after you take it out. I have a dowell. I marked and labeled with a number of my barrels. It can sometimes be a real surprize to know the true length too.

Those Marlins have 16 1/2" barrels, I almost bought one a couple of years ago. This link says a 24" barrel makes the 45ACP quiet, but that's a relative term. http://www.rhinelandarms.com/MAUSER/...onversions.htm

My intention is a backyard gun to compliment the 26" 10/22. I'd like to call that pack of yotes in one night and teach the survivors a lesson about my property. :uzi2: The gun doesn't have to be truly silent, just .....well.....polite. :grin:

Uh oh, I had to come back and edit this. Seems like the barrel on that Mauser conversion that was labled "quiet" by the manufacturer is 16 1/2" as well. I asked a guy with a 24" Mauser 45ACP conversion how loud his is yesterday and I'm still waiting for a response.

Hey! I like that idea. I am thinking of converting an old mauser I have here. Guess I had better make me a receiver wrench.

I don't put much faith in that Mauser conversion manufacturers claims. First they claim that it's quiet, and Prebancolt tells us his sounds similar to a .22. More telling is the claim that it increases velocity by 300 fps. :rolleyes: Nah, I don't buy that one a bit. Looking at the barrel nut on that Mauser gave me a DUH moment, I've got a Savage. I'm sure Pac-Nor would make me a barrel, not sure what I'd do about a magazine though.

I assume that the extra barrel length would slow down the velocity, and that would hurt trajectory of that short 230 gr hollowpoint. So, since I want the velocity as close to 1000 fps as possible I'd try +P or even 45 Super (in a Marlin using a 22# Wolfe spring) loads, hopefully that fast burning powder would still burn up. There's probably a compromise point between barrel length, loading, and noise and that's what I'm looking for.

So, the question stands, how long of a barrel? Anybody have a .45 muzzleloader with a long barrel thats willing to pull apart a ACP cartridge and front load it?:smile:

I think there should be some point that the powder/ power/ noise curves would be optimized. It wouod be noice to experiment with it. That punkin' ball coming at you would always get attention.

Guys,

I'll TRY to remember to measure the length on my barrel tonight. 16 1/2 seems about right, though.

Got some pesky beavers that need attending to this afternoon. I'm thinking about trying out my new 300 whisper with the Sierra 220gr RNSPs (subsonic, of course). Wouldn't want to scare them while I was, well, killing them.:grin:

Jerry

I love it when I can brag about having a new gun too.

I really like the way you all think... The trick with a really long barrel will also be accuracy as the subsonic 45ACP will be in the tube a fairly long time so recoil and the like will affect the usefullness some... The same concept could be used for other small powder charge rounds... 300 whisper with a 26-inch barrel perhaps?

It does sound like a fun project and I wonder about the old "revolver" style rifles... what if you took something like a Ruger Blackhawk with the 45ACM/45Long Colt conversion and built it into a rifle like this... A stiffer 45LC would give better distance performance while the 45ACP would be quite with the obvious noise from around the cylinder.

I wonder if anybody does conversions like that? Regardless, a T/C Contender or Encore barrel might be one of the cheapest ways to try a project like this but I guess any rifle barrel could be shortened if you later decided you didn't like it...

Good luck and sure does sound like fun!

Some time back I remember readinga n article ina magazine where the author took a long barreled rifle and began cutting it in incriments then measuring noise and velovity as well as accuracy. It was interesting even if it destroyed a good barrel. I wonder if anyone has done that lately?

I agree, the best way is probably to have someone make a .45 barrel for a Marlin, Savage or Mauser and test it. A chronograph would be helpfull too. Use hot loads and keep cutting off an inch until the sound level reaches your goals. At that point you should be able to use lower pressure loads safely and quietly.

Remember, Prebancolt said his 16.5" Marlin was quieter than his 18.5" Ruger 10/22. I was assuming 26" would be necessary but now I'm thinking 24" might do it.

BTW those guys that used 26" or longer .22LR barrels said that they are SILENT except for the sound of the hammer dropping and the bullets impact. Nice but I don't need to go that far.

There are 1911 colt and Glock pistol conversions, they claim a velocity increase also. I'd belive it with P+ or 45 Super ammo but I'd doubt it standard pressure ammo. http://www.mechtechsys.com/ They don't say anything about noise with thier 16.25" barrel.

Besides using a muzzleloader, another cheap way of testing barrel length is a chamber adapter in a .45 caliber rifle like a 45/70, I read an old poster saying these guys will make one but I didn't see it listed. http://www.mcace.com/adapters.htm I asked that poster how long his barrel was and how loud it was with the adapter but he hasn't responded yet either.

I just found something interesting.
http://www.taurususa.com/products/pr...category=Rifle
I'd heard it was coming out but I didn't know it had a 26" barrel. Lyman sells cast bullets in weights from 292 to 535 grains.

Reminds me of the old Winchester pump 22 I learned ot shoot with and they later copied.

I'd rather have a long barreled Marlin Camp 45 but I might get one of these and see if the long barrel quiets those 45ACP pressure loads. Winchester has factory 225 gr HP Long Colt loads at 930 fps that are pretty close to a .45ACP load.

Looks like these are in demand so I could always find someone to resell it to. I might even decide I like the slide action enough to keep it.

I finally got a response from a guy shooting standard pressure 45ACP from a rifle. It was CCI Blaser 230 gr with the brass case, Midway says 850 fps from a pistol. I asked him about his gun and how loud it is. Heres his answer.

" Thomson Center G2 with a custom 25 inch barrel.
Noticably quieter than a pistol, but still loud."

He also reports a 210 fps INCREASE for an average of 1060. Hmmm, real close to supersonic. I'll bet lighter loads or faster powder would quiet it down some more.

It would be nice to have sound readings in db to know what it actually was at the muzzle. Then the subjective would be quantified.

"Silence is golden"
 

First..thanks to Bigfoot for bringing this forum/thread to my attention...

Next...I've been working out a plan to use pistol ammunition in a long barreled rifle for a bit now...doing a lot of reading on the issue. Goal is to put a lot of energy on raccoons/feral critters out to max 100 yards, but do it quietly. Also looking at suppressed rifles/300 whisper, but if the long barrel/light load will do the job without the NFA..I'm for it.

Interesting info here http://guns.connect.fi/gow/ed.html as well as on the rest of the Gunwriters on the Web site. I don't reload as yet, so am looking at what loads are commercially avaiable that use heavy bullet with light load. Like to keep this all "off the shelf". Looking to read reviews on the Taurus.

I had a 27 inch fast twist 44 mag barrel built for my TC Encore. I use 310gr lead bullets and relatively fast 231 powder. I cronograph them to make sure they stay at about 1000fps. They are pretty quiet for having that much knockdown. I don't need hearing protection at all to shoot them. I would say that it is similar to a 22 rifle in sound. I am getting about 1.5 inch accuracy at 100 yards. It was an interesting experiment even though the barrel maker probably though I was crazy for spending my money on it. For me, it was worth it to find out.

I made a barrel for an old 12 ga. single shot 1920's era shotgun in 45acp about 10 years ago. At that time i had ffl and was doing this type of stuff. used a douglass blank and made the barrel 18" long. Drilled and tapped for a scope shot dmn good. I hated to give it back, but it was for a friend. Don't remember the acoustics. Probably a bit less then pistol sounds. Had an exposed hammer. Wasn't trustworthy for modern 12 ga shells,but 45 acp was no problem.Yeah I wish but I got a marlin camp carbine. Its just not as accurate.regards.

Most people that I've talked to agree with JF about the sound level. A bit louder than I expected to discover but that's life.

I won't be getting a Taurus Thunderbolt afterall since the sound level question has been answered. There are several reviews on them over on The High Road forum.

I've decided to play around with a Hi-Point .45ACP carbine when they come out. The price of the gun AND a longer barrel should be about the same as an unmodified Marlin Camp .45. Cheap, accurate, reliable and a no questions asked lifetime guarantee too.

I've been wanting to do the same,,,,
 

and any .243/260/308 bolt face rifle [Ruger 77 Mark II] will do,,single shot tho probably.
It would be the 'CB cap' of the 45 ACPs.
Lots of 45ACP ammo out there to play with, too.
I can't bring myself to spend the $$ for a 45ACP play toy,,,yet. I have the lathe and reamers,,just need a barrel.
Alan in GA.

Effectively, what you are going to produce is something similar to a Deslisle carbine.
Why not trying to do someting using a longer case , of similar volume as the 45 long colt to launch heavier bullets like a .458 500gr bullet? The 45 automag case for exemple? reamers and reloading dies existe and cutting down a 308 case is very easy to form the brass.
That should be more effective.And would look les ridiculus in a standard bolt action. Actualy you should be able to feed from it.

Regarding the barrel, a cut rifled barrel with a 1in 12 " twist should do.

ND

or the 45 Win Mag would work, too.
 

Had a Contender 14" barrel in 45 Win Mag,,it's loaded HOT in factory ammo. Would feed better, too.
But then I built a .458 American [.458 x 2"] on a short action Ruger 77 [open up bolt face, polish feed rails, grind and polish extractor lip, etc] ,,so I am still twidleing in the .45 caliber realm with not much direction. Might bring me back to the little .45 ACP again. Just thinking.
Alan in GA.

You're right, it would be more powerfull and have better range and I considered that. Lee makes some bullets molds that I like. 500 gr HP with a .443 BC, I've forgotton the BC for the 405 gr HP right now. These could used with soft lead and a gas check for good expansion at these low velocities so they would really thump game and should penetrate fine also.

I decided on the ACP because of the guns intended use. At 100 yards (the length of my property) the higher BCs arn't really necessary. For my game 230 gr HP bullets are plenty powerfull and I don't want any extra penetration for reasons of safety. Factory 45ACP 230 gr ammo is already loaded to the proper velocity and is cheap. Coyotes travel in packs so at close range I want a fast repeater and the Tunderbolt pump 45LC is a top eject which I dont prefer, I don't tend to like lever actions either.

Cartridge???????????
 

Hey Guys....I've been keeping an eye on this discussion for a while. Ironically I've been looking at a custom barrel in 45ACP for my Contender carbine but looking at the possibility of say 480 Ruger. I want to launch large bullets at subsonic speeds. The 45ACP is a no brainer since ammo from factory is subsonic.....the only thing stopping me going ahead is the idea of a 400gr 475cal bullet from the 480 Ruger at 1,000 fps! Question is would a 230gr 45 ACP bullet have enough energy to dispatch a hog at 75 yards???? I know 400grains surely would!

Hello to you guys, (I mean the three last persons that answered my post).
Here are some of my thought regarrding the subject:
If you are willing to use 45 acp, that is fine, the round is subsonic, the rifling twist is perfect for the 230gr bullet, the choice of bullets is great. Only ploblem, except the marlin rifle, and a few others (I have seen lee-enfield actions converted to take colt mag and feeding reliably, like a deslisle), your options are going to be prety limited to single shot . The contender barrel would be great for that purpose.
If you are going the contender way, than a barrel in 45 long colt is the way to go because you can launch heavier bullets(in the 45LC range) that WILL stabilise properly because the twist and the weight of the bullet MATCH.(twist in 45LC is arround 1 in 14 or 16 if Iam right).

Now if you had a barel in 45/70,here are the problems that ocur: the twist for that caliber is quite often 1 in 20, which is good to launch heavy bullets(400grains for exemple) at super sonic speed. But these same bullets would not stabilise at subsonic velocities in the same barrel.

So a barrel specialy made with a twist of 1 in 12" (more or less) would help to stabilise these bullets at subsonic speed.

Now, I do not like lever action either.
So I would go for the bolt action option.

I do not like beleted cases and rimmed case in a bolt action (also the belted can work very well).

I think that the ideal shape of the case would be a rebated case that would fit a standard bolt action face(.308), that would have a small case volume, similar to a 45 LC, a shoulder (20-25 degres for exemple) for reliable feeding, a good long neck to help hold these big long bullets (case neck lenght> bullet diametre).

Now I am not trying to reinvent the 458 socom, but almost. A 284 winchester case, shortened would be the idea, specialy with all the good quality brass available from lapua and hornady in 6.5x284.

There is another case similar to that idea called the 45 blaser. but its capacity is to large, it is design for supersonic speeds. but is gives an idea of what it would looks like.
have a look at :http://www.municion.org/45blaser/45blaser.htm


Of course, that baby needs a special reamer, a special set of dies, a custom barrel... etc
But having spent a lot of money in another projet in the past ( ruger 77/44, with silencer) and not obtaining the good results Beacause the twist and quality of the barrel where not up to it, made me think.

Let me know what you think.

ND

short rimmed cases,,bolt actions,,,
 

You made me think of one that already exists,,,the Rem 788 in 44 Rem Mag. It feeds, and is very accurate which means it must have the correct twist at least for the standard weight bullets.
I'm gonna make this interesting and cloudy up the waters even more: I want a .458" bore. I enjoy shooting paper patched bullets in a few rifles I've owned :45/70s, .458 WIn Mag [Ruger 77 Tropical], .458 American [.458 x 2"] in a Ruger 77 short action with a converted Ruger #1 barrel that was a .45/70 barrel [worked great]. I also had a Contender Super 14 in 45 Win Mag. I have envisioned a shortened 45/70 case as a new single shot pistol/carbine [Contender] round that would be the right powder capacity[?] case for a subsonic .458 bore barrel.
There are some "ready to patch and shoot" bullets for any .458" bore cartridge: the Speer 250 gr swaged SWC bullet meant for pistols of .451-.452" caliber. Any lead [soft] pistol bullet meant for the .451" bore ctgs patches GREAT up to about .460" for any of the .458" bore rifles/single shot pistols.
Here's my 'made for picture' 45/70 x 1.5" round I thought might get me into a .458" bore
Contender barrel allowing paper patching--->

Have you heard of the 458 socom? Uses 308 case head specs so 308 bolts would work. brass is available and reloading dies. It is mainly used in ar15 ,but
bolt actions rifles can be done. Problem is you can't get reamer for it. You would have to go thru the creator teppo jutsu and order a barrel.regards.

paper patch bullets for .458" bores...
 

here is the 250 Speer SWC swaged FACTORY bullet. Also one I recovered from an 8 pt buck after penetrating about 24" [entered rear of abdomen, travelled thru and out of chest,,entered and stopped by left front leg which was amazing to be able to recover the bullet!].
The middle bullet is a 325 grain meant for .45 Colt also. The last is a .358" meant for the .358 Winchester rifle I once had.
Alan in GA

Cartridges
 

The 1 1/2" 45/70 is listed in Cartridges of the world as the 45 Silhouette. Could be interesting if you wanted to sling some 500gr bullets down range.
I've just found out that 45 cal is the largest to do safely on the Contender action. Which brings me back to using the 45ACP if I want to use factory ammo alreadly subsonic or the 44 Magnum or 45 Colt if handloading. I've read about good results of the later two with bullets in the 300gr range. Question is what would be the correct twist rate to use to accurately pitch 300gr 44 or 45 cal bullets at subsonic speeds? I think the norm for the 44 mag is 1-20 so maybe a 1-16 might improve things.

The 45/70 shortened down is a good idea for the contender.

I am not sure but can one of you confirm the base diametre of the .458 socom? I thaught it was the same as a 7.62x39 and not the 308.
The 308 version has another name I believe.
I am not sure that the bolt head of an m-16/ar-15 can be opened to accept a .308 diametre case, that why the socom base is designed smaller.

Regarding the 44 mag with 300gr bullets, I do not think it will work in a barrel with a 1 in 16 twist for the following reason: The 1 in 16" is what is used in 44 special, which in turn uses a much shorter and lighter bullet(200-210 gr) launched at subsonic velocities.
I have a program somewhere to caculate the proper required twist, but I haven't any of the Hornady 300gr on hand.
I would guess that 1 in 12 or 13 should work just fine.
ND

I've never been on a hog hunt so I don't know if a standard .45ACP would be enough. I know that a Marlin 45 Carbine will handle +P and .45 Super ammo with a stiffer Wolfe recoil spring, I'm hoping the Hi-Point will also. The .45 Super with 255 grain hard cast bullets should be enough, but if not look into the .460 Rowland it's about even with than the 45 LC. Load data is pretty scarce but here are some 260 grain loads from a handgun, add a couple hundred FPS for a carbine length barrel. Make sure to click the load data at the bottom. http://www.realguns.com/archives/106.htm

Here's a 1911 Colt carbine conversion for it. http://www.mechtechsys.com/index.html

I ran the Rowlands 1:16 twist into an online twist calculator and it said it should stabilise really long bullets. I'm not sure that I trust that calculator, it might not be accurate at handgun velocities. http://www.shortmags.org/shortmags/r...stRateCalc.asp Remember that the longer barrel will stabilise a bullet better than a short handgun barrel with the same twist.

Alan, what was the velocity of that 250 grain Speer SWC and the range of the deer? Nice performance.

Theres the heap of info at this link http://www.teppojutsu.com/458.htm
Makes me think that the 1 1/2" 45/70 could be fun. The case capacity is looks close to the socom, cases are easy to get and will suit the contender. The above web site lists that a 1-14 twist will handle 500-600gr bullets at sub speeds even with a short barrel. Anybody have a link to a twist rate calculator to confirm what barrel twist would be required if I went down the 1 1/2" 45/70 route with 500-600gr bullets at sub speeds?

I will try to put my hand on a very good one i have somewhere on my computer.
Far better than the greenhill formula.

ND

The 458 socom has the same head size as the 308 or base if you want to call it
that.The ar bolt can be machined to .510" which is about the max.Tromix made and sold ar's in 50 AE which has the .510 dia bolt faces. It required a special extractor. So does the socom. Machining the ar bolt to .510 leaves a paper thin
amount of material from the original round part. The bolt held up to the pressures and worked.The biggest cal in an ar15 is the 510 phantom. It is 510 cal same blank as 50bmg. The bolt face is .530".to do this they use olympic
arms wssm parts.The bolt.bolt carrier,upper and barrel extension are redesigned
and bigger then the standard ar15 parts. I had the opportunity to examine a wssm barrel recently.regards.

Hello tp555,
I guess I was wrong about the rim dimension. Sorry for that.

Murmur, I have a twist calculator, unfortunatly, it's creator does not which me to give it away on the web.

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

Whats up fellows. Didn't realize it had been so long since I last visited here. I see you are on one of my favorite subjects again but don't forget one of the oldest rules about the sound level of subsonic ammo. The sound pressure level is directly proportional to the cross sectional area of the bullet or in other words .45 is one of the hardest ones to quiet and .17 is one of the easiest. Fast burning powder in a long barrel will get you started and most go middle road with 9mm or 308 to get the quietest with the most energy delivered to the target. One of the cheapest to try is an old sks with the gas piston removed shooting 308 150gr and up with a fast pistol powder. Always check for a clear bore after each shot until you are sure of the load and wear eye protection (the sks gas tube vents to the sides and rear unless packed or plugged).

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?

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.

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?