Switchblock Gas port Diameters for 300 Whisper/Blackout ???

[binder]

What about modifying the adjustable gas block from the Robinson armament XCR? Doesnt seem it'd be a huge problem to modify it to accept a gas tube. I've had an XCR and the gas system worked wel.

[DEF23]

Only Noveske makes a Switchblock(R).

You are incorrect, sir. Noveske makes the "Switchblock" whereas there are other companies who make 'multi-position, switchable gas blocks' (like Paladin, as an example).

The Noveske system really doesn't interest me in the least, as I have had far too many friends who have had issues with theirs, under 'real world' conditions.

Also, it cannot be tucked up under a set of hand-guards (MK12 style) and if it does fit it is a bear to adjust, even with modified factory wrench. (I would have added some straight slots to the front of the knobs and stippled the gripping surface on them, IN ADDITION TO THE WRENCH, myself).

The biggest problem being that BOTH the JP and Cliq-block are made to rely on set-screws, so it is going to fail sooner or later, as a by-product of it's adjustment design (set screw/threads).

And all of them (with the exception of some JP's) are going to wear out faster than the host weapon due to the make-up of their construction material (aluminum or stainless steel VS. tool steel).

Yes, that is why not a single company (or maybe not a single company with more than one employee) offers 300 BLK with an adjustable gas system.

That is kinda funny, because I see a least two different manufacturers who offer piston driven 300 BO's. And I also have a friend who has an almost 20yr old upper (Whisper of course, not BO) from JD Jones himself with a 4 position, switchable gas block on it.

You also can't say it is under-gassed or choking for more when there are people out there putting drop-in piston systems on gas-operated pistol caliber AR carbines and getting them to function just fine.

And then there all of the guys who have built gas-operated AK's in pistol caliber rounds with no issues at all and all that with a round with 1/2 the charge weight of a 300 BO, pushing a bolt that is weights a lot more (originally) with a gas port that is a lot further away.

Just some things to think of, sir.....

......You should NEVER say that something can't be done or that isn't warranted......

Otherwise far too many things would have never made it off of the R & D shop floor..........LOL !!!

Tell ya'll what, as soon as I begin to get this thing up and running I'll post some info/pics and let ya'll know how it turns out.

[300Blk]

Only Noveske makes a Switchblock(R).

You are incorrect, sir. Noveske makes the "Switchblock" whereas there are other companies who make 'multi-position, switchable gas blocks' (like Paladin, as an example).

Paladin makes an adjustable gas block. Noveske owns the name Switchblock. It is not correct to call anyone else's adjustable gas block a Switchblock.

http://tess2.uspto.gov/bin/showfield?f= ... cbubca.2.1

[300Blk]

That is kinda funny, because I see a least two different manufacturers who offer piston driven 300 BO's. And I also have a friend who has an almost 20yr old upper (Whisper of course, not BO) from JD Jones himself with a 4 position, switchable gas block on it.

I realize Whisper(R) needed adjustable gas blocks because there was no ammo standard, but it is not needed for 300 BLK because the ammo being sold works without one.

[300Blk]

That is kinda funny, because I see a least two different manufacturers who offer piston driven 300 BO's.

Not sure what this means. Piston does not require an adjustable gas system either.

And then there all of the guys who have built gas-operated AK's in pistol caliber rounds with no issues at all and all that with a round with 1/2 the charge weight of a 300 BO, pushing a bolt that is weights a lot more (originally) with a gas port that is a lot further away.

I never said piston cannot be done. I had one made and this is me shooting it:

http://www.youtube.com/watch?v=7Eb5fwPNH9c

[-k-]

If you want to use 300 BLK spec subs there is no need for an adjustable gas system.

If you want to handload subs with faster powders (300W/30-221) you should get a pistol gas system, carbine gas 16" will probably not work.

[DEF23]

Paladin makes an adjustable gas block. Noveske owns the name Switchblock. It is not correct to call anyone else's adjustable gas block a Switchblock.

IMHO, I would call the Paladin an multi-setting gas block, not nessacairaly an adjustable one. As once it's drilled and mounted, there isn't any room for adjustment --- only the different settings.

I realize Whisper(R) needed adjustable gas blocks because there was no ammo standard, but it is not needed for 300 BLK because the ammo being sold works without one.

Come on now, if all of the specs were concurrent across the board for the 300 BO, then why do some people have issues with a "brand X" barrel, at 'such-and-such' diameter gas port running subs, while the next fella will slap his build together using the same barrel and his will run like a charm with everything ???

If you want to use 300 BLK spec subs there is no need for an adjustable gas system.

I just want to be able to use the widest range of ALL ammo variations, Whipser, Blackout, 300-221 or otherwise.

If you want to handload subs with faster powders (300W/30-221) you should get a pistol gas system, carbine gas 16" will probably not work.

_________________
Todd
Noveske Rifleworks

Is this due to the "burn-off" rate by the time the gas makes it back to the BCG ???

Or are you worried about the pressure drop once it reaches the muzzle ???

Just some random questions.......

Also, kinda wondering what would happen if you lightened the BCG itself to overcome the initial inertia of un-locking (ie shave a few oz.) ???

I am doing a sub-sonic 7.62x25 Tok/AK-74 build right now also and found out that once I got rid of a few extra oz. of BCG weight, she runs like a champ.

You guys think you have gas issues --- I ended up needing a .152" gas port for .308 bullet......LOL !!!

[-k-]

The 16" carbine gas port is about as large as possible, because there is much less pressure to capture than there would be with a 5.56. The 300 BLK subs have more pressure at the gas port than the older sub loads, so they cycle very close to the supersonic.

You won't have a problem with supersonic running too hard, unless you open the port for old sub loads. The simple solution is use the 300 BLK subs rather than complicate the gas system, but if this is something you just want to tinker with I recommend you start with a pistol gas 16" barrel so you have more room to adjust the gas port up.

Lightening the operating mass or reducing the action spring strength can cause a failure to feed, if the rifle doesn't have the energy to strip a round out of a full mag.

[300Blk]

I realize Whisper(R) needed adjustable gas blocks because there was no ammo standard, but it is not needed for 300 BLK because the ammo being sold works without one.

Come on now, if all of the specs were concurrent across the board for the 300 BO, then why do some people have issues with a "brand X" barrel, at 'such-and-such' diameter gas port running subs, while the next fella will slap his build together using the same barrel and his will run like a charm with everything ???

A few barrel companies made their barrels in a way that I would describe as being incorrect.

[Whole Bunches]

And all of them (with the exception of some JP's) are going to wear out faster than the host weapon due to the make-up of their construction material (aluminum or stainless steel VS. tool steel).

Interesting sentence you wrote. What are the signs that your gas block is wearing out? Even if a gas block wears out, how many rounds would that take before the user noticed it? The PRI adjustable gas block on my 10.3" 300 BLK upper is made from 1141 steel. I've fired it 2651 rounds, and the gas settings I'm using are the same as when it was new. The KIES adjustable gas block is made from 4140 steel. KIES will be putting their adjustable gas block on their 300 BLK build, and I have one on my .223 upper. Based upon what you've said, gas blocks ought to wear out even faster in caliber .223/5.56mm guns, as the pressures and amounts of powder used are higher than 300 BLK subsonic loads.

I'm interested in this subject, as I keep records on rounds fired through my .223 and 300 BLK rifles, including measuring the throat erosion.