Suppressed 45 cal thumper ideas

[tommag]

A good friend and I have debated the perfect suppressed set up for quite a few years. Given the low velocity needed, we figured a 429 to 454 cal would be the best, along with a large meplat. He decided to submit his paperwork for a 45 cal can this week. 500 s&w is ruled out because most of the 50 cal cans are for the bmg, big and expensive. He is looking at an encore bbl chambered in 45 colt from mgm. I figured I could make some dummies for mgm to throat the bbl for optimum fit.
I like the 350 gr noe mold, but it isn't in the files I downloaded to quick load. I figured it wouldn't be too hard to push this boolit to 1050 fps in an encore. It would be over saami pressures, but I don't think that would be a problem in an encore.
We debated the 300 whisper and ruled it out, based on a 30 cal maybe tumbling, maybe not. The idea is for a relatively short range, reasonably quiet thumper that would give good penetration and maximum leakage on deer, pig, and black bear sized critters.
He's looking at an m4 style grip for the encore, along with the sig brace to build a psuedo sbr that would be in compliance with current atf rulings and still be compact, maybe a 10" bbl.
Anxiously awaiting the thoughts from this knowledgeable group.

[475AR]

A good friend and I have debated the perfect suppressed set up for quite a few years. Given the low velocity needed, we figured a 429 to 454 cal would be the best, along with a large meplat. He decided to submit his paperwork for a 45 cal can this week. 500 s&w is ruled out because most of the 50 cal cans are for the bmg, big and expensive. He is looking at an encore bbl chambered in 45 colt from mgm. I figured I could make some dummies for mgm to throat the bbl for optimum fit.
I like the 350 gr noe mold, but it isn't in the files I downloaded to quick load. I figured it wouldn't be too hard to push this boolit to 1050 fps in an encore. It would be over saami pressures, but I don't think that would be a problem in an encore.
We debated the 300 whisper and ruled it out, based on a 30 cal maybe tumbling, maybe not. The idea is for a relatively short range, reasonably quiet thumper that would give good penetration and maximum leakage on deer, pig, and black bear sized critters.
He's looking at an m4 style grip for the encore, along with the sig brace to build a psuedo sbr that would be in compliance with current atf rulings and still be compact, maybe a 10" bbl.
Anxiously awaiting the thoughts from this knowledgeable group.

While I have not played with the 45LC, I do alot of suppresed development with 45acp and 45 win mag. I settled on 2 cast bullets the first is an LBT 280GR LFN and the second is an accurate molds bullet I designed http://www.accuratemolds.com/bullet_detail.php?bullet=45-300H-D.png
I stayed @ or under 300gr so I could use both bullets in the acp. What length barrel is he planning to run? Also what can will he be using? Both of those questions have a big inpact on sound suppression. In the LC a 350gr bullet @ 1050fps is not hard but you need to choose powder carefully. I find that a powder that burns 95-100% at the end of the barrel gives best sound, yes you could use a fast powder depending on the barrel length. Do you guys have access to Quickload? If so it will be a big help in working up loads with specfic bullets and powders.

[mcdaniel.mac]

I went with a .460 SW Katadyn encore barrel so I could still throw big bullets fast, but could also chuck subsonics. As soon as my stamp gets approved (September? October?) I'll let you know what suppressed well, but for now it shoots 255gr cast lead just fine over 8.0gr Unique. Extracting .45LC empties is a pain, so the next round will be loaded deep into a .460 case. I have a recipe scribbled in the back of my Lyman's manual that calls for 10.0gr of Titegroup bhind a 395gr LFP at 1100FPS in a .45LC case and marked with the words ENCORE ONLY. I've not been brave enough to try it but supposedly it works fine in a well-built rifle. I have a small bag of 440gr PC bullets that I intend to try over Unique as well.

My plan is to stick to PC lead or copper plated to keep my Hybrid cleaner.

[tommag]

I have ql, but the file for the 350 wasn't in my download file from noe. I had picked a 10" bbl from my hat, figuring the expansion ratio of the 45 colt wouldn't add anything with a longer bbl. I don't know what can he's planning on buying, but he mentioned visiting them in Austin, Tx., next week while on a business trip.

[tommag]

While I have not played with the 45LC, I do alot of suppresed development with 45acp and 45 win mag. I settled on 2 cast bullets the first is an LBT 280GR LFN and the second is an accurate molds bullet I designed http://www.accuratemolds.com/bullet_detail.php?bullet=45-300H-D.png
I stayed @ or under 300gr so I could use both bullets in the acp. What length barrel is he planning to run? Also what can will he be using? Both of those questions have a big inpact on sound suppression. In the LC a 350gr bullet @ 1050fps is not hard but you need to choose powder carefully. I find that a powder that burns 95-100% at the end of the barrel gives best sound, yes you could use a fast powder depending on the barrel length. Do you guys have access to Quickload? If so it will be a big help in working up loads with specfic bullets and powders.

That's a good point I had not considered regarding powder burn percentage at the bbl length. I'll keep that in mind while playing with Ql.

[tommag]

He's looking at buying this suppressor.
https://www.silencershop.com/silencers/large-bore/bowers-vers-458.html?

[475AR]

Playing with the noe .452-342/ 452-350-PP bullet you can go with N105 and hit 1092fps @ 21500 psi and is a 99.16% burn with muzzle psi of 2482. Looks interesting to start with.

[HATCH]

I have a yankee hill sidewinder 45 can.

It is great with a little water in it on my 1911 shooting 230 gr RN lead
It does OK with 40 cal out of my UMP shooting 180 grain lead (@1100 fps)

I haven't tried it with 9mm yet

[lar45]

Here is the print for the NOE 454-350
http://noebulletmolds.com/NV/images/N.O.E._Bullet_Moulds_454-350-RF_(GC)__Sketch.Jpg

[IraqVet1982]

He's looking at buying this suppressor.
https://www.silencershop.com/silencers/large-bore/bowers-vers-458.html?

This is too much can for a subsonic 45LC load. I'd go with a modular and user serviceable 45 cal (pistol) can. You'll get a lot more use out of it.

[tommag]

This is too much can for a subsonic 45LC load. I'd go with a modular and user serviceable 45 cal (pistol) can. You'll get a lot more use out of it.
It looks like too much can for this project, but he's thinking on using it on a couple different bbls. I don't know about user servicable. If it's a sealed unit, it doesn't look like a good candidate for cast boolits.

[Outpost75]

Accurate 45-290H with 3.5 grains of Bullseye in .45 ACP brass, 700 fps from 20" barrel, exits bore every time, does not need a "can" to be quiet. Accurate enough for 100-yard head shots in 20-inch twist barrel.

199337

[Artful]

It looks like too much can for this project, but he's thinking on using it on a couple different bbls. I don't know about user servicable. If it's a sealed unit, it doesn't look like a good candidate for cast boolits.

Bowers Vers 458 is NOT user serviceable - you can clean a sealed suppressor - but you will have to do it in several steps -
1) to get rid of lube use boiling water soak
2) to get rid of powder / carbon solvent soak
3) to get rid of Lead - the very dangerous "DIP" (Don't expose you skin to it)
(make sure to properly dispose of used product)

[M-Tecs]

I am thinking about doing are canned thumper also but it will be on an AR platform in 458 SOCOM or a 450 Bushmaster.

http://www.joeboboutfitters.com/Radical_Firearms_16_458_SOCOM_COMPLETE_Upper_p/rf-upper-fhr16-458.htm

[tommag]

Accurate 45-290H with 3.5 grains of Bullseye in .45 ACP brass, 700 fps from 20" barrel, exits bore every time, does not need can to be quiet. Accurate enough for 100-yard head shots.
I bet that is quiet. A mouse fart in a longer barrel is a much simpler approach.

[milsurpcollector1970]

My vote is for a 45 acp with a can on the ar-15
I just bought a dedicated lower receiver which takes grease gun mags
Planning on reaming it out to 460 Rowland so I can hunt with it

[Digital Dan]

Not picking on anyone or anything necessarily, but there be a few things to ponder here. A subsonic thumper is a bit of an oxymoron. Placement is key to success with subs and it doesn't matter a lot what the caliber or bullet form. Flat point bullets still generate supersonic flow field velocities at 1050 fps. They do get quieter around 950-1000 fps.

[Kosh75287]

Flat point bullets still generate supersonic flow field velocities at 1050 fps. I'm glad you said that. 1050 f/s seemed a little close to the sound barrier, to me.

If the rounds are to be used in a single-shot, a projectile with better ballistic coefficient could help offset trajectory issues with 900 - 1000 f/s loads. Might also dissipate the supersonic flow field velocities encountered with the flat-points (guessing).

[Digital Dan]

Having problems with the computer at the moment and can't put a picture up. Try a search here on the site for .30 Sneezer and there might be a picture of a bullet that does ok at 1050.

[Outpost75]

I bet that is quiet. A mouse fart in a longer barrel is a much simpler approach.

The 20" barrel is mild, but my Beretta 912 folding shotgun with .45 ACP with 28" barrel is REALLY quiet without a can...

199370

Here you can download an MP3 with sound showing how quiet the rifle is:

http://www.hensleygibbs.com/edharris/movies/Rook_bunny.avi

[tommag]

Not picking on anyone or anything necessarily, but there be a few things to ponder here. A subsonic thumper is a bit of an oxymoron. Placement is key to success with subs and it doesn't matter a lot what the caliber or bullet form. Flat point bullets still generate supersonic flow field velocities at 1050 fps. They do get quieter around 950-1000 fps.
Good thoughts. In using the term thumper, in thinking of max penetration, energy transfer, and leakage. I figured a large meplat with a fair bit of weight would maximize effectiveness given the velocity restrictions.

[tommag]

The 20" barrel is mild, but my Beretta 912 folding shotgun with .45 ACP with 28" barrel is REALLY quiet without a can...

199370
That looks like the ultimate bloop tube!

[Digital Dan]

Tommag, in the subsonic realm energy transfer isn't really worth consideration if for no other reason than there is little to go around. Accept the idea that with placement one can disrupt the neural network or circulatory plumbing and little more. Think in terms of how the bullet will behave as it penetrates. Straight path or a wandering version? Set aside the conventional metrics (SD, FPE, etc ad nauseum and think like an archer.

[Digital Dan]

.30 caliber, 183.5 gr, 30:1 alloy: There is no noticeable difference in sound footprint at 900-1050 fps

http://i.imgur.com/ejIij4M.jpg

.44, 320 grains, 30:1 alloy: 900-950 is quiet, 1050 cracks.

http://i.imgur.com/7Hk8Q6C.jpg

[Billythepoet]

Look at the Liberty Cosmic. I really like mine. It's a serviceable can, that's rated for 22lr-44mag. It can handle a few low pressure rifle rounds as well. My .45acp Mauser sounds like a pneumatic brad nailer. I haven't gotten around to loading for my Ruger 77/44, but 44spl is just as quiet as the 45acp.
Hopefully I can get some heavy subs loaded soon. I've got 240, 300 and 320gr bullets to play with.

[Smoke4320]

First make sure he gets a can up to the job. A 45 acp can is NOT approved for anything hotter than a 45 ACP. Applications are currently running at ONE YEAR (ask me how I know).

yes sir 11-12 months is common right now for approval

[Smoke4320]

.30 caliber, 183.5 gr, 30:1 alloy: There is no noticeable difference in sound footprint at 900-1050 fps

http://i.imgur.com/ejIij4M.jpg

.44, 320 grains, 30:1 alloy: 900-950 is quiet, 1050 cracks.

http://i.imgur.com/7Hk8Q6C.jpg

That's some purrty bullets right there

[rockrat]

yep, last approval took 361 days

[Artful]

http://img.photobucket.com/albums/v355/rowdyfisk/Misc/Hartikka_bullet_noise_graph.gif (http://smg.photobucket.com/user/rowdyfisk/media/Misc/Hartikka_bullet_noise_graph.gif.html)

The larger the projectile's sectional area the more noise it will make moving thru the atmosphere, as more air has to be displaced by the projectile. - 38 caliber and smaller make much more quieter suppressed weapons.

[Billythepoet]

http://img.photobucket.com/albums/v355/rowdyfisk/Misc/Hartikka_bullet_noise_graph.gif (http://smg.photobucket.com/user/rowdyfisk/media/Misc/Hartikka_bullet_noise_graph.gif.html)

The larger the projectile's sectional area the more noise it will make moving thru the atmosphere, as more air has to be displaced by the projectile. - 38 caliber and smaller make much more quieter suppressed weapons.


True, but I can tell you from experience that subsonic 45acp and 44mag , from a bolt gun, are noticeably quieter than subsonic 9mm through a semi auto pistol. They are probably quieter than a semi auto 22. That's by the human ear, not decibels. They are very quiet.

[Artful]

Locked breach will funnel all gases down thru the suppressor - semi Auto's won't
38 special is equivalent to you 9mm

https://www.youtube.com/watch?v=I-knJmz6HE0

[Artful]

Doesn't sound bad in even in 45 caliber can

https://www.youtube.com/watch?v=Nwm_XC5OHQA

[Billythepoet]

Locked breach will funnel all gases down thru the suppressor - semi Auto's won't
38 special is equivalent to you 9mm

https://www.youtube.com/watch?v=I-knJmz6HE0

Exactly. I just wanted to make sure that OP want scared away from the suppressed thumper idea, thinking it would be substantially louder than a small bore. It is really easy for people to get hung up on decibels, when the sound at your ear is what you are chasing.

[Artful]

https://www.youtube.com/watch?v=5onQdyY8_1M

[tommag]

This has been a good thread for me. You guys have answered questions I didn't even know I had.

[Digital Dan]

Artful's post above with the graph is telling in many ways, but there are aspects not fully addressed. The speed of sound (Mach) is somewhat variable due to atmospheric variability. It is somewhat faster in hot air than cold, and likewise in dense air. Engineers look at temperature at the calculation pivot mostly.

The salient aspect of all this is what is called the transonic velocity range, or roughly Mach .8 thru 1.2, or the region of highest drag coefficient. Why? It takes energy to compress air, that being the vehicle which leads to a sonic shock wave and the associated sound footprint. That energy bill is paid by the velocity loss as your bullet wanders thru the maze.

So, your bullet may be subsonic in chronograph measure, but the catch is that the air flow around the bullet doesn't see it the same way. As the bullet passes by it has to move around the bullet (flow field) and acceleration is largely defined by how far it has to move to do that. My opinion mostly, guided somewhat by experience, very blunt nose forms or flat meplats are the worst culprits in generating more noise and they do this due to the drag coefficient attendant to those designs. I don't think caliber is the cause nearly as much as the nose form. Support for this idea is found in BC calculators when proper numbers are used for a given bullet and a series of velocity adjustments are utilized. When one begins to drop out of the transonic realm, BC starts to climb briskly, hence, drag is way down. The .30 cal bullet pictured above has a calculated BC in the high .3 range at 1050 fps. The .44 mag bullet, noticeably lower...at that velocity. It picks up a fair bit in the 900-950 fps zone.

[Artful]

https://www.youtube.com/watch?v=bYpVuK0KW_c

[Artful]

Artful's post above with the graph is telling in many ways, but there are aspects not fully addressed. The speed of sound (Mach) is somewhat variable due to atmospheric variability. It is somewhat faster in hot air than cold, and likewise in dense air. Engineers look at temperature at the calculation pivot mostly.

The salient aspect of all this is what is called the transonic velocity range, or roughly Mach .8 thru 1.2, or the region of highest drag coefficient. Why? It takes energy to compress air, that being the vehicle which leads to a sonic shock wave and the associated sound footprint. That energy bill is paid by the velocity loss as your bullet wanders thru the maze.

So, your bullet may be subsonic in chronograph measure, but the catch is that the air flow around the bullet doesn't see it the same way. As the bullet passes by it has to move around the bullet (flow field) and acceleration is largely defined by how far it has to move to do that. My opinion mostly, guided somewhat by experience, very blunt nose forms or flat meplats are the worst culprits in generating more noise and they do this due to the drag coefficient attendant to those designs. I don't think caliber is the cause nearly as much as the nose form.

Support for this idea is found in BC calculators when proper numbers are used for a given bullet and a series of velocity adjustments are utilized. When one begins to drop out of the transonic realm, BC starts to climb briskly, hence, drag is way down. The .30 cal bullet pictured above has a calculated BC in the high .3 range at 1050 fps. The .44 mag bullet, noticeably lower...at that velocity. It picks up a fair bit in the 900-950 fps zone.

Actually if you reexamine the graph - it tracks two sets of data
- they used same caliber bullets and just the nose shape was changed

notice little significant difference in the noise generated.

Schilierian bullet shockwaves from below to faster than the speed of sound...

http://accurateshooter.net/Blog/litztrans1501op.png

http://technophilicmag.com/wp-content/uploads/sites/3/2013/12/refractive.png
Super vs trans speed of same bullet

If you are in the pits and some shooters are shooting .22 caliber and some are shooting .30 caliber you will notice a significant difference of the sound of the misses
- the hits all sort of sound alike going thru cardboard or hitting wood.

But if you are down range and someone is firing a .45 caliber it sounds quite loud compared to the 30 caliber and even more so compared to the 22.


https://www.youtube.com/watch?v=QhlxH9XDW_A

[Digital Dan]

Wasn't arguing against you, trying to point out the implications of transonic velocities. This is reflected in your graph but not annotated in any particular fashion.

[Artful]

Just trying to explain the graph and enlighten those who have not delved into Sub/Trans/Super sound problems. The graph was actually made in Finland
for explanation of the noise factors at the gun range and what a suppressor
on a firearm could eliminate and what it couldn't.

[Digital Dan]

You did well on that to be sure, but as learned from McCoy and Vaughn, it ain't as simple as A-B-C. Too often when graphics are presented to illustrate a particular factoid, there be more there for the taking if one has a broad understanding. Too many shooters are not educated on many of these issues and thus leap to erroneous conclusions.

One of the photos you posted illustrated the oddities as well as anything. It was indicated to be subsonic, yet had the shock wave...on the base, and not the nose. One of those "Oh no, Mr. Bill!" moments to some I suppose.

Just lending a helping hand as it were.

[Artful]

One of the photos you posted illustrated the oddities as well as anything. It was indicated to be subsonic, yet had the shock wave...on the base, and not the nose. One of those "Oh no, Mr. Bill!" moments to some I suppose.

Just lending a helping hand as it were.

Are you refering to this picture?
http://accurateshooter.net/Blog/litztrans1501op.png

Remember you are looking at a fixed frame and may not "see the whole picture"
the "bow" wave of compressed air may be far enough forward as to be out of the
frame.

I always enjoyed these types of photo's

https://www.youtube.com/watch?v=bELu-if5ckU

[Artful]

https://www.youtube.com/watch?v=DD53Er62GrE

[Artful]

The fun will be when we design a projectile that's 45 caliber but with a nose
to make it's sonic boom as quiet as 22LR supersonic

https://www.youtube.com/watch?v=HGQvNYmVZBE

[Artful]

https://www.youtube.com/watch?v=L_64FHDKN1I

[Digital Dan]

Are you refering to this picture?
http://accurateshooter.net/Blog/litztrans1501op.png

Remember you are looking at a fixed frame and may not "see the whole picture"
the "bow" wave of compressed air may be far enough forward as to be out of the
frame.

I always enjoyed these types of photo's

https://www.youtube.com/watch?v=bELu-if5ckU

That type of imagery is quite informative.

Yes, that was the pic I referred to, point being it is M0.98 and has a shock wave. It isn't a on or off thing, this "subsonic" world.

[Billythepoet]

Shot my 1911 with a GemTech 45 suppressor on it using 1150 fps defense loads today. Quieter but you still need ear plugs. Suppressed is NOT silenced ! No 458 "thumper" will be that quiet unless way subsonic.

Is that a 9mm 1911? 1150 is pretty fast for a 45acp. Either way, subs from a bolt action are completely different than subs from a semiauto pistol.