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I found Franklin armory selling out a 24" 6.5 Grendel barrel that said was a type 1.
In doing a bunch of reading, I'm not 100% certain I'm tracking on what bolt is going to be compatible. (They stopped making their own bolts, so I can't get theirs and it's no longer on their website.)
Would the Alexander Arms bolt work? A standard 7.62x39 bolt would work?
Before I take the plunge and put it on order, I just want to make sure I'm not making a mistake.
Thank you!
Posts: 6,206
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03-15-2019, 05:01 PM
(This post was last modified: 03-15-2019, 05:15 PM by VASCAR2.)
Type 1 bolt signifies .125 bolt face depth and 7.62x39 AR-15 bolt. Aim Surplus 7.62x39 bolts get good reviews as do LMT x39 bolts.
Black Hole Weaponry marked their 264 LBC barrels as Type 1/Type I if they used a .125 bolt face depth 7.62x39 bolt. BHW marked their barrels that were chambered to use .136 bolt face depth 6.5 Grendel bolts as Type II. Other manufacturers started using the same nomeclature to identify which bolt was appropriate for their barrels.
https://aimsurplus.com/aim-ar-m16-7-62x3...rier-group
Here is a link to Toolcraft BCG, I have no connection with either retailer.
https://www.armorally.com/shop/toolcraft...ier-group/
Posts: 25
Threads: 5
Joined: Jul 2018
First, I really appreciate the information. I put a toolcraft 7.62x39 on order.
But now I'm confused and a bit disappointed when I heard this back from Franklin. (They sold their Grendel barrels out at $99, only to find out they quit making the matching bolts. Which I didn't know at the time I ordered them.
This is what they just sent:
Quote:Our barrel is made for a standard Headspace bolt measurement about .124. This does mean it is a type 1 bolt. We can't recommend using a 7.62x39 bolt. Sorry that this will make finding a bolt difficult.
Thank you
That is a type I bolt right?
At this point, I'll cut my losses and have an excuse to build a 7.62x39 AR and dump the barrel.
Posts: 6,206
Threads: 50
Joined: Mar 2011
You really need to rent a set of head space guages or read up on how to check the chamber head space. Most bolt face depths are + or - .001 tolerance maybe more. Franklin CS are probably trying to CYA. The 7.62x39 bolt face is .125 spec but there are tolerances. If you choose to go this route and the tolerances are off a finish reamer might solve the problem. Since you already ordered the bolt it can’t hurt to check to see if it is compatible. Unless they have gone to a completely different type of barrel extension I can’t see how the 7.62x39 bolt might allow you to use the barrel.
At $99 and the price you have in BCG your still not out a large some of money if you didn’t make a good purchase.
