What makes a Gas Block so special?

[aleaddict]

I've always used quality parts for my builds... Giessele triggers, Rainier match barrels, DD uppers and handguards to name a few. I never think twice about spending $50 on a gb... until now.

On a whim I purchased a low-profile gas block from Red Barn Armory for $20, which included a gas tube and pin (Black Friday special). I thought for $20 delivered it was worth a shot. I was afraid it would not slide over my match barrel or the gas hole would be too small or misaligned... some machining flaw or quality control issue lurking just around the corner. To my surprise it fits perfectly. No burrs or sharp edges. All holes line up correctly. The only thing I don't like about it is the semi-gloss melonite finish. Other than that I am very pleasantly surprised.

So my question is what makes a name-brand gas block worth twice as much money as a generic one? Most descriptions I've read only mention "high quality steel" and "extremely tight tolerances" but no mention of the steel alloy used or where it was produced. Other than looks and logos, is there really that big of difference between gas blocks? I just want to ask before pinning it to my brand-new bbl.

-- ale

[smac61]

As far as I can tell, you wont get the satisfaction of saying "...and a XXX gas block" when describing your build. Having said that, women get wet when I mention my Vltor LP clamp on...

EDIT: I only buy well established, proven parts for my builds anymore. The money isn't that big a factor, I know I'm getting quality and it makes me happy. If I ever sell one of my builds, the potential buyer will have no doubt as to the quality of the gun down to every pin and spring.

[Hmac]

The quality of any manufactured item has multiple components, largely engineering, construction, and quality assurance. The engineering of a gas block is no big trick, assuming they're using good quality material. Where a company will cut corners on such an item, if they didn't cheap out on the steel, is in the construction and most importantly in the quality assurance. They may use crappy mills, or not replace their bits often enough, other things, but if they have a qood quality assurance program, the consequences of corner-cutting in the construction will become apparent and the item will be tossed. So, IMHO, the question becomes, how many of the units do they actually check the specs on, what do the define as acceptable tolerances, and what do they do with the ones that are outside those tolerances? The more they inspect, wider their quality tolerance, the more they throw away from being outside tolerance, the more money it costs them and the more they have to charge.

IMHO, a $20 gas block has a higher chance of being out of tolerance because they either didn't check it or their tolerances were looser than, say BCM or VLTOR. I buy gun parts from a given company based on the likelihood that I'm going to get a good unit (lower, upper, BCG, RE, barrel, gas block, etc). Granted, if you happen to get a $20 gas block that's actually in spec....bonus, bacause you got a useable part for cheap. Personally, I would rather spend the extra money and take less of a chance.

[Iraqgunz]

Actually the Vltor block and some others are made from 17-4PH stainless. Sadlak blocks are made from 1018 alloy steel. Things you need to be concerned or aware of are the actual material construction, that the gas block set screw alignment holes are correct, proper heat treat, proper ID for fitment to the barrel, not to mention the orifice for the gas tube. All of these things matter and of course you won't know it, until you purchase your 20.00 gas block.

It's kind of like everything else out there, if you feel comfortable with the gas block, you can keep your gas block.

[aleaddict]

Thanks for the quick replies. It forced me to check the fitment between the gas tube and block... something I hadn't considered when I started this thread. Yup, it was a tight fit. I ran a drill bit by hand into the gb to remove any hidden burrs. After that the gas tube slid all the way in. I lined up the cross pin and drove it through. At this point everything seems gtg.

My question about gas blocks is not about saving money but evaluating parts based on function over hype. A lot of firearm parts these days are made using Metal Injected Molding (MIM), which 10 years ago was seen as a poor substitute to steel billet. Now you'll probably find MIN'd parts in all but the most expensive 1911s. I look at the FSB/GB of an AR-15 and its nothing more than a casting... surely my $20 gb is a step or two above a casting lol...

[Airhasz]

Advantage of paying for name brand GB is knowing it will fit and perform and not wondering what is going to show up in your post box.

[bigwagon]

I look at the FSB/GB of an AR-15 and its nothing more than a casting... surely my $20 gb is a step or two above a casting lol...
The mil-spec ones are forgings and they don't cost much more than $20.

[Rayrevolver]

https://www.m4carbine.net/showthread.php?149806-Gas-Block-Failure

[BufordTJustice]

Advantage of paying for name brand GB is knowing it will fit and perform and not wondering what is going to show up in your post box.
This. I can build a rifle or rec a part from a reputable manufacturer and know they won't make me look like as horse's ass due to fitment, materials, or QC issues.

[aleaddict]

Copy all that... I can see that everyones mind is already made up.

[smac61]

Copy all that... I can see that everyones mind is already made up.

Thats how it works...

[steyrman13]

I have a gas block on an upper that was built by someone else using mostly quality parts, but the gas block is unknown. All three set screw holes are stripped out on it so it will either need some helicoils or trash it