school me on adjustable gas blocks

[Robb]

http://www.midwayusa.com/product/775...er-steel-matte

Can an adjustable gas block, like the above PRI, completely shut off the gas turning your gun into basically a bolt action?

[Tim K]

Not sure about that one, but mine from JP will. My guess is that the one you linked will, too.

[Robb]

Good to know. Really it isn't necessary but I'm in the middle of a 6.8 build that my kids may use for hunting. Son has taken 3 deer and one antelope with a bolt action but the daughter hasn't gotten anything yet. I was here at work thinking maybe it would be nice to have the ability to make it a single shot but keep ammo in the mag, just starting out.

Any downsides to the adjustable block? I just have a standard weight carrier.

[Hoser]

The PRI blocks are good, I use one on my OBR in 260.

However, if you plan to turn the gas on/off or up/down a lot they are evil and will bite you in the end.

A pure on/off/suppressed like a Noveske switchblock is a little more bulletproof.

[Fromk]

One thing to be aware of is that there's going to be a lot more gas coming out of the muzzle and it's going to get loud. I have a properly adjusted gas block (also JP) and a muzzle brake that makes life pretty miserable for anyone standing on either side of me. It is going to be very intense with ALL the gas coming out the end.

That is a very creative and interesting plan to use one, though.

[Robb]

I just thought with all the excitement during a hunt and with teens, it may be worth the money to temporarily covert it to single shot.

Hoser, I'm dense, I don't get this: "However, if you plan to turn the gas on/off or up/down a lot they are evil and will bite you in the end." I'll check into the Noveske here in a few.

Fromk, As far as loud, it should only be a handfull of shots at most hunting season and then back to normal semi-mode. Cant be worse than the bolts we normally shoot.

Edit: Just looked at the Noveske, very nice and just what I think I need, On&Off. Ummm, anyone know of a less pricey knockoff?

[MarkCO]

First, the vast majority of the adjustable gas blocks will NOT turn the gas completely off. The JP, PRI, Seekins, Syrac, etc. WILL NOT turn off the gas. They will reduce gas flow, in most cases, to the point that there is not enough gas to force to cycle and or even unlock the bolt. That is the biggest problem as you will get gas cutting, then leakage and then gasblock failure if you use an adjustable and adjust it frequently and even more so if you turn it all the way in. Adjustable gasblocks are more of a "tuneable" gas block. I had high hopes for the Syrac, but it is failing more and more frequently, especially with people who adjust them frequently, and it leaks pretty bad.

The Noveske swtchblock does not have these issues, so it is the one to get if you want to turn the gas off...there are no others that are worth messing with.

A better solution would be to mod a bolt by cutting the distal flange off the gas ring journal and use no gas rings. Just a bolt swap and you are good to go.

[Robb]

Didn't think about that, modding a bolt is do-able.

MarkCO, you make the statement that no other adjustable block other than the Noveske are worth messing with. Does that include the TeppoJetsu-Paladin? I know nothing about them and just found them doing a search. They don't seem to have any bad reviews that I've found so far.
http://www.teppojutsu.com/
The Gen 4 would be prefect for me. On/Off. Price mentioned in some threads is substantually less than Noveske. However if it doesn't measure up I'll think about the Noveske or the bolt mod.

[sportbikeco]

All this sounds like a solution to a problem that does not exist. Also you give up any recoil reduction the semi auto action provides.

[Robb]

It is a problem that doesn't exist I suppose, but I feel better with the kids hunting with a semi in being able to shut the gas off for a few years. Shit does happen and I want to do as much as possible to assure it doesn't happen to me & mine. This probably won't work for most but i think it will work for me.