Silencing a 45/70-dimensions to apply for?

Yes, it can be legal to make a silencer. For everything Form-1, from silencer designs that are easily made, to filing forms with the BATF, to 3D modeling. Remember, you must have an approved BATF Form-1 to make a silencer. All NFA laws apply.

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Elkins45
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Silencing a 45/70-dimensions to apply for?

Post by Elkins45 »

A local sporting goods store has the H&R Handi-Rifles in 444 Marlin and 45/70 on sale for $199. I couldn't resist, so yesterday I plunked down the cash for a 45-70. Now I am feeling the urge to make a Form 1 can to shoot subsonic with it. I figure a 400 grain soft lead bullet at 1000fps would be an excellent quiet 100 yard whitetail gun.

The question is one of dimensions: how long and how wide would a clipped cone 45 caliber rifle can need to be to be hearing safe with subsonic ammo? I was thinking of submitting my Form 1 for 12 inches but if experienced people say that I can do it with a shorter tube I'm not married to the idea. I do know that it's OK if the final build is slightly shorter but never OK if it's longer. Would filing for 12" and then building at 10" be something ATF would frown upon?

If I do this I will undoubtedly cut the barrel back to 17". If I were made of money I would cut it back to 10", but maybe that's a project for the future?
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curtistactical
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Re: Silencing a 45/70-dimensions to apply for?

Post by curtistactical »

For sub sonic loads just to be hearing safe 12" is way overkill. I would go around 1.75" OD x 8" it should be quiet and still not be too cumbersome in the field.
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Re: Silencing a 45/70-dimensions to apply for?

Post by mscott »

curtistactical wrote:For sub sonic loads just to be hearing safe 12" is way overkill. I would go around 1.75" OD x 8" it should be quiet and still not be too cumbersome in the field.
I agree. I have a form 1 filled out with those very dimensions in mind. Only difference is mine will be a .50 cal in case I ever get an itch for a .500 S&W.
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T-Rex
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Re: Silencing a 45/70-dimensions to apply for?

Post by T-Rex »

mscott wrote: in case I ever get an itch for a .500 S&W.
Why would you want to silence the beast :D

Mine used to breathe dragon flames :twisted:
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Elkins45
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Re: Silencing a 45/70-dimensions to apply for?

Post by Elkins45 »

I went ahead and filed my Form 1 this morning for a 10" length.

Interesting statistic: the time between the email stating my application was "PENDING RESEARCH" and the one stating it was "SUBMITTED/IN PROCESS" was a whopping 17 minutes.
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Re: Silencing a 45/70-dimensions to apply for?

Post by mscott »

T-Rex wrote:
mscott wrote: in case I ever get an itch for a .500 S&W.
Why would you want to silence the beast :D

Nine used to breathe dragon flames :twisted:
We just got a law passed and now we can hunt with cans, so just planning ahead.
I'm working on a .460 S&W bolt gun that is somewhat of a dragon itself.
Elkins45
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Re: Silencing a 45/70-dimensions to apply for?

Post by Elkins45 »

My form 1 is back-40 days including the Christmas holiday.

What thread should I use? I know it doesn't matter as long as the gun and can match, but I might like to buy a 458 SOCOM AR upper some day. A bit of searching makes me think most are 5/8-24 just like 300 blackout, correct?
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Re: Silencing a 45/70-dimensions to apply for?

Post by silencertalk »

5/8-24 is unsafe as someone could mount a 30-cal can.

I would think 5/8-32 is correct for that.
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Re: Silencing a 45/70-dimensions to apply for?

Post by Bendersquint »

silencertalk wrote:5/8-24 is unsafe as someone could mount a 30-cal can.

I would think 5/8-32 is correct for that.
1/2-28 is unsafe for 9mm as someone could mount a .223/5.56 can.

A certain amount of user self responsibility is required.
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Re: Silencing a 45/70-dimensions to apply for?

Post by silencertalk »

Colt used 1/2-36 and that would have been a nice standard 9mm size, but companies did 1/2-28, so it is the most common for 9mm now.

If everyone with a 458 Socom was using 5/8-24, then fine, but 5/8-32 is the established size for big-bore ARs as far as I know - you should double check before picking it.
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Re: Silencing a 45/70-dimensions to apply for?

Post by Bendersquint »

silencertalk wrote:Colt used 1/2-36 and that would have been a nice standard 9mm size, but companies did 1/2-28, so it is the most common for 9mm now.

If everyone with a 458 Socom was using 5/8-24, then fine, but 5/8-32 is the established size for big-bore ARs as far as I know - you should double check before picking it.
All of my 458SOCOM's are threaded 5/8-24 from either TeppoJutsu or SBR.
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Re: Silencing a 45/70-dimensions to apply for?

Post by T-Rex »

Wilson sells them 11/16 x 24
Tromix has 5/8 in both 24 & 36
RRA sells them in 5/8 x 32

OP, it seems you have 3 popular choices.
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Elkins45
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Re: Silencing a 45/70-dimensions to apply for?

Post by Elkins45 »

Well, since I already have a 5/8-24 tap from making my 300 blackout flash hider its a pretty easy decision.
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Re: Silencing a 45/70-dimensions to apply for?

Post by gunny50 »

T-Rex wrote:Wilson sells them 11/16 x 24
Tromix has 5/8 in both 24 & 36
RRA sells them in 5/8 x 32

OP, it seems you have 3 popular choices.

45 caliber? well I would go M16x1 either Left or right handed.
For rifles with bull barrels even M18x1.

a lot of people above make notes on what could be mounted if a certain thread was used.
But take a look at some of the silencers on the market with QD mounts.
A lot of the manufacturers use the same MB or FH with the same specs in both 556 and 762.
And than we all expect the user to be smart enough not to place a 556 can on a 762 host.
What to think about the Mounts that use the standard 22mm FH.


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Re: Silencing a 45/70-dimensions to apply for?

Post by T-Rex »

gunny50 wrote:
T-Rex wrote:Wilson sells them 11/16 x 24
Tromix has 5/8 in both 24 & 36
RRA sells them in 5/8 x 32

OP, it seems you have 3 popular choices.

45 caliber?
Gunny
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If we wanted to talk 45 caliber, you can add .578 x 28, .575 x 40 and 7/8 x 9 (for MAC 10/45).
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Re: Silencing a 45/70-dimensions to apply for?

Post by gunny50 »

T-Rex wrote: 45 caliber?
Gunny
.458Socom
If we wanted to talk 45 caliber, you can add .578 x 28, .575 x 40 and 7/8 x 9 (for MAC 10/45).[/quote]

Yup I do understand but it started all with 45/70 Right?
and 5/8 is smaler than 16mm so I do not see any problems there. ;-)
Most barrels in .458 Socom might be over 18mm so I would opt for the M18x1.

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Re: Silencing a 45/70-dimensions to apply for?

Post by Wicked »

I use 3/4"-28 threads on 458 Socom bull barrels that are 1.0" diameter at the muzzle.
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