Do size matter??? Gasblocks

[Brianma65]

So , what do a Low profile GB do, that a Regular GB won’t.

I have a 20 inch .556 barrel ordered and it’s coming with a .936 GB.
Should I go with a low profile?

Thanks

 

[Trinimon]

Low profile if your handguard length extends past the length of your gas system. This so that the GB can fit inside the handguard.

 

[Brianma65]

Low profile if your handguard length extends past the length of your gas system. This so that the GB can fit inside the handguard.

That part I understand

So most handguards will not clear a high profile GB?
Are the GBinside or outside measurements ?

 

[jiffx2781]

That part I understand

So most handguards will not clear a high profile GB?
Are the GBinside or outside measurements ?

Advertised gas block measurements are the inside diameter where the gas block fits the barrel.

Another way to explain it is that if you have a barrel that has a diameter of .936" where the gas block fits than you would need to buy a gas block that is advertised as being a. 936" gas block.

The type of gas block or external dimensions is irrelevant to the advertised diameter as that only refers to the diameter that fits the barrel.

 

[Brianma65]

OK, got it.
So from the pic ,would this be a low profile?

 

[Kratos]

Yes, as long as there isn’t an FSB or rail then it’s low profile. Low profile is basically for free float handguards and FSB is for the standard 2 piece handguards.

There’s also an inbetween which is a railed gas block, so you can mount a front backup sight on the gasblock similar to an FSB. It would normally use the 2 piece handguard as well.

 

[Brianma65]

Excellent, thanks