Reducing length of existing barrel...

[too_many_hobbies]

My 300 Fireball is dedicated to subsonic ammunition and is never used without the sound suppressor. After predator season ends this month, I plan to have the barrel shortened to reduce the overall length of the weapon to make it more convienent to get through the woods, to transport, and to improve the balance. It presently has a 16" Olympic Arms barrel. The functioning gas block is actually beneath the hand guard. The one seen in the picture beyond the hand guard is fake. I plan to do away with it during the barrel shortening process.

What reduced length is recommended (10.5", etc.)? Any disadvantages to a shorter barrel? Will the gas port have to be relocated after the barrel is cut off? I am familiar with applying for a tax stamp for a sound suppressor. Any details to applying for a short barrel rifle? Can I go ahead and apply now so I will have the permit by the time I get the barrel back from the gunsmith?

[cav_scout_tj]

Originally Posted by too_many_hobbies

What reduced length is recommended (10.5", etc.)? Any disadvantages to a shorter barrel? Will the gas port have to be relocated after the barrel is cut off? I am familiar with applying for a tax stamp for a sound suppressor. Any details to applying for a short barrel rifle? Can I go ahead and apply now so I will have the permit by the time I get the barrel back from the gunsmith?

According to the ATF, you MUST submit and receive back your Form 1 to Make a Short Barreled Rifle before you possess the parts to make a short barreled rifle. So if you are gonna do an SBR, start that first so that can go through the ATF pipe while figure out what length you want a get the smith to work on your barrel. You will also need to get your lower engraved as part of the SBR process, and that takes time too to send off and stuff.

How long is up to you, you can get up to max subsonic in a pretty short distance. 10" is a good number, you could go a little shorter or a little longer. I think around 7" is the shortest you can go and still get the gas system to function.

I have a 9.5" 300 whisper barrel on order, it should be on a lathe about now. I already have a registered SBR with a 10.5" 5.56 barrel. The 5.56 runs great. I can't say the 300 mine runs yet, but I'll post when I get it put together. I went with a .100 gas port and adjustable block.

You will probably want a pistol position gas port-- if you dont already have one.

[320pf]

I would not cut that barrel. I would get another barrel and have that one cut

If you are looking for a good price on a barrel, I would order one from Tony at Del-Ton. The last time I talked with Tony (Del-Ton) his barrels are 16-in. and cost ~$180... Cut the barrel to 10-10.5 in. and move the gas port to the pistol position. The Olympic Arm gas port is about 0.5" closer to the chamber than the standard pistol position. But I would go with the gas port in the standard pistol position.

320pf

[AlcoholicusMaximus]

I am waiting for my form 1 to come back.I planned on having my model 1 .300 fireball cut & threaded @ 10.5", but would rather just buy a new barrel set up that way. The ATF person I spoke with said that the engraving was to be on the barrel. Noveske Rifleworks has a new 3 position gasblock for suppressed weapons that is making me think twice about my next barrel purchase

[steezo757]

Originally Posted by AlcoholicusMaximus

I am waiting for my form 1 to come back.I planned on having my model 1 .300 fireball cut & threaded @ 10.5", but would rather just buy a new barrel set up that way. The ATF person I spoke with said that the engraving was to be on the barrel. Noveske Rifleworks has a new 3 position gasblock for suppressed weapons that is making me think twice about my next barrel purchase

I was hoping they would make an adjustable gb. But I'm not sure it'll work for me. Per the pic below, it doesn't look like it'll fit underneath a FF handguard. Most people with .300 Whisper/FB barrels have a pistol length gas system. That'll require us to use pistol length FFs.

Someone sent me a PM earlier in the week about having a custom adjustable gas block made. I'll probably persue that ave.

[Spook]

totally off topic....where are you that they allow you hunt with a suppressor?

[WhisperFan]

Originally Posted by too_many_hobbies

What reduced length is recommended (10.5", etc.)?

I like a 10.5" Whisper. I started out with a RRA 'pistol only' AR in 223. Since it was an AR pistol, I was obviously allowed to have the shorter than 16" pistol length barrel on it. I bought a M1 Sales carbine length 300/221 upper for it.

Originally Posted by too_many_hobbies

Any disadvantages to a shorter barrel?

None I can think of - especially if you plan to keep it as a dedicated subsonic firearm.

Originally Posted by too_many_hobbies

Will the gas port have to be relocated after the barrel is cut off?

I also wanted to shorten my barrel to 10.5" after I SBR'd my RRA lower. I moved my gas port to a pistol length position for this modification.

Originally Posted by too_many_hobbies

I am familiar with applying for a tax stamp for a sound suppressor. Any details to applying for a short barrel rifle? Can I go ahead and apply now so I will have the permit by the time I get the barrel back from the gunsmith?

The rule of thumb is that if you have the ability to assemble what you own into a legal configuration - you are OK. In other words, if you have a short barreled upper, but you do not own an AR pistol or an SBR (or MG), you have no way to assemble that upper into a legal firearm. If you own that upper and a Title 1 rifle lower, the ATF can assert that you are in 'constructive possession' of an unregistered SBR.
Now - if you have an SBR, an AR machinegun, or an AR pistol, you can own as many short uppers as you desire. You are allowed to have more of them than you have lowers to mount them on. As I understand it, you don't have to have enough parts to assemble them all at once into legal configurations, but you do have to be able to mate each upper to a lower one at a time and keep them legal.

Now - if you have a friend or relative that does not own any AR lower at all, they are allowed to own a short barreled upper, since that upper is not the registered part and is not (by itself a firearm) they are not in possession of anything other than 'gun parts'

Lastly, in regards to engraving your name, city and state on your lower: Many people are of the mind that they do this in advance of the Form 1. The reasons are that there is no law that states that you can't engrave your firearm with your name, city and state (even if it is not an NFA firearm.) That way, before you get your Form 1 approved, the receiver is a Title 1 firearm. Since it is not an NFA firearm, it does not fall under the provisions of the NFA in regards to shipping. If the engraver screws it up, you haven't already sunk your 200.00 into it. If you have to ship it somewhere else for re-finishing, that's cool too. Lastly, if (God forbid) it gets lost, you aren't looking for an NFA firearm and you aren't out your 200.00

Then - once the engraved receiver comes back and is in your hands, you can file your Form 1 and once approved, it never needs to leave your hands again.


Remember - the engraving needs to be no smaller than 1/16" high and no less than .003" deep. Many people think that the laser engravers are not deep enough. I used stamps and stamped mine - but often the finish will flake if you use stamps - then you really need to refinish it.

Hope that all helps