help please, thickness (diameter) of threads in mounting cap

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mr fixit
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help please, thickness (diameter) of threads in mounting cap

Post by mr fixit »

Im down to the last piece of my F1 can. I am about to turn the rear cap, and want to make it with an integral comp. What I want is basically this below from an older thread of Samson's:
Samson1044 wrote:using 316 SS (even 304) as your blast baffle material would work fine and I doubt that you would ever wear it out unless you spend as much shooting as you do on your house note or unless you are running it full auto all the time. 17-4 is surely stronger that 316 but unless you have it on hand I wouldn't bother.

By using Grade 9 titanium tube and grade 5 for your end caps you would drop a lot of weight , you could even use 7075 aluminum for you caps and save more weight , use a brake style adapter and that would save even more wear on the blast baffle.
Like this http://www.griffinarmament.com/Griffin- ... -p/tmm.htm

if you made the first 3 baffles out of out of SS and the rest from 7075 you would still get thousands and thousands of rounds out of it before you started to even see any wear on the aluminum baffles and after a couple years and 4,000-5,000 rounds if they were worn you could just replace them (assuming you are not in the US because that would be against the law especially if you went around telling people about it:wink:)

Fabricate your spacer as part of your cone , this will help with strength if you went with aluminum and help with tolerance stacking and any possible bore misalignment
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If you decide to make your rear cap from steel then you can mill or cut the meat from between the thread root of the threads to drop some weight , and even make a brake into it which is not that hard on a mill with an indexing head. for threaded caps I prefer to cut my female barrel threads first then make a male stub piece , thread it on in the chuck and then thread the male tube threads , this will ensure perfect alignment between the bore and tube threads. you can also final bore your brake exit in this setup and ensure perfect alignment and run a smaller exit bore.
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on a bolt gun you will be hard pressed to get the temperature of a suppressor to 600-700 deg which will keep the aluminum in the threshold of its strength range.
My next form 1 will be made from all 7075 aluminum except for the first baffle , I plan to use a commercial threaded brake/mount from either TBAC or Griffin. I'm gonna run it on an 18" AR-10 and see how many rounds it take to get it to 700 deg and try to keep it at an elevated temperature each time I shoot so I can guage the strength and erosion of the aluminum.

That's just my 2 cents
My question is about the thickness of the material around the mounting threads for the barrel. This will be direct thread, welded can, 1.625"OD 1.505"ID, 4140 tube and caps. Can is for 16" .223 rifle.
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T-Rex
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Re: help please, thickness (diameter) of threads in mounting cap

Post by T-Rex »

Just make the OD of the brake portion the same as the barrel or .75".
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Capt. Link.
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Re: help please, thickness (diameter) of threads in mounting cap

Post by Capt. Link. »

Keep the barrel as thick as possible and end the cap as stiff as possible.No reason to thread just use a light press fit and weld.
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