No M.A.R. AR vise block

[ks_wayward_son]

I am in need of a vise block to complete an AR build, and have settled on this set after researching.

https://www.ebay.com/itm/NO-M-A-R-AR...YAAOSwuYVWn9in

My question is do/have any of you used the NO M.A.R. system for barrel installation/basic builds? Are the plexi glass supports absolutely necessary? Also, what is the purpose of the pins in the vise block?

Thanks.

[DubC-Hicks]

Have you considered just doing a magpul BEV block? I've used mine countless times and never had a problem. Love that thing.

No experience with the one you listed, I just like the idea of supporting the barrel itself like the BEV block and Geissele reaction rod.

[turtlehead]

I have a clamshell type that doesn't mar. Has held up great so far after a dozen barrel installs.

[FrankenMauser]

Stoner's original design involved assembly with the barrel clamped in a vise block, and the receiver free-floating.

Upper receivers, takedown pins, and barrel extension pins were never intended to take the load we put on them today with clamshells, BEV blocks, mag well blocks, and picatinny rail clamps.


That being said...
I'll use a clamshell or my picatinny rail clamp before something that engages the barrel extension (like a BEV block). When you torque a barrel and use the barrel extension as the support, ALL of the torque applied is going through one little pin that was only designed for two simple jobs: to keep the barrel extension from rotating on the barrel, and to align the barrel with the upper receiver.
It's a similar situation with anything that grabs the upper receiver, but at least the torque is applied to aluminum and steel, rather than between two steel layers.

The number or reports of sheared barrel extension pins has risen dramatically since the BEV block and similar tools became popular...

[turtlehead]

That's a good point on the barrel vise. Any recommendations? Be nice to have for muzzle devices, too.

[FrankenMauser]

That's the rub...
A lot of barrel contour and barrel nut configurations don't let you clamp in a spot that has a large enough diameter for "cheap" barrel vises to grab the barrel.

The best option if using a good, strong vise, is a set of aluminum V-jaws (and some powdered rosin -- it'll look like crap, initially, but cleans up easily).

[DubC-Hicks]

How would a reaction rod differ from clamping the barrel itself? I've torqued down to 70ish lb-ft with no problems with the BEV block.

[ks_wayward_son]

I agree with the vise clamp jaws. No MAR actually makes a set that looks very durable.

https://www.ebay.com/itm/NO-M-A-R-4-...item3f8c1b93fb

It has the groove to specifically support the barrel. Thought it would come in handy when installing a muzzle device or even swapping out sights in handguns.

[T. O'Heir]

Those are two different things on Evil-Bay. Neither is a barrel installation vise. The first is for holding the receiver/lower without crushing it. The blocks in the second one are blocks to hold a barrel in a vise while you work on the barrel itself. Not the same thing as a barrel vise that holds the barrel at the chamber while you screw on the receiver.

[ed308]

How would a reaction rod differ from clamping the barrel itself? I've torqued down to 70ish lb-ft with no problems with the BEV block.

Clamping the barrel works great. But the receiver not so well. You can damage the upper receiver or shear the barrel index pin at that level of torque. The Reaction Rod grabs at the barrel extension which is installed on the barrel at much higher torque.

NoMar, clam shell and etc, they all work. Just be careful with the level of torque. Trust me, you can cause damage to the upper or the pin at torque levels that are less than 70 lbs. I've done it and learned the hard way. I now use either a Reaction Rod or Brownell's Rod for all of my installs.

[rickyrick]

I don’t know, but I used the BEVblock several times and it works well. But... big but... you have to have a bolt carrier to get it to work.

[DubC-Hicks]

Exactly, the BEV block and reaction rod support the barrel extension, and don't allow the barrel to twist and shear the pin. I see a device that supports the extension to be better than a clamshell.

[FrankenMauser]

BEV block/reaction rod let the upper move freely until the nut gets snug. But, at that point, all of the torque being applied through the threads twists the upper receiver against the BE pin.

If you hold the receiver, less force is transferred to the pin ... as long as the nut and barrel extension shoulder were lubricated properly.


Pick your poison.

[ks_wayward_son]

It would seem the Bev Block sounds likes a pretty good solution, but what Franken said about all the torque being applied to that little pin gives me pause. However, all the solid reviews of the Bev seems like it is a viable option. I guess no method is going to be absolutely without risks, or maybe I'm just over-analyzing. As was mentioned...pick your poison, eh?

As a side note, what do you use for proper anti-seizing thread lubrication? I've read that specific thread grease (i.e. Aero Shell) isn't the only grease that will work. I have some Lucas Red and Tacky that is anti-seize. Figure that would work as a pretty decent all-around smithing grease?

[ed308]

Aero Shell. You can get it on Amazon.

[DubC-Hicks]

Aeroshell is the expensive way to go it. I use Valvoline moly-fortified white lithium grease. Used it lots of times, and always works well.

I don't think anti-seize is the way to go. IIRC, it can cause corrosion between steel and aluminum. Could be wrong, but I do remember people saying to not use it.

[ed308]

There seems to be some misconceptions about the Reaction Rod and especially the Super Reaction Rod, which is the one I use. I purchased my Super Reaction Rod after I sheared a barrel extension pin with a clam shell. It sheared because the torque applied to the barrel nut was transferred to the pin, upper receiver and clam shell. If your putting a lot of torque on the barrel nut to get it to index, you run the risk of damage. Here's what the Super Reaction Rod manual states about stress on the index pin:

"The Super Reaction Rod was designed with the advanced armorer in mind, an armorer who frequently works on AR15/M4 platforms with over torqued, seized or Loctited barrel nuts. The Super Reaction Rod works by pre-loading the barrel nut extension to the
lugs of the Super Reaction Rod to eliminate any movement before adding torque to the barrel nut, while at the same time fixing the upper receiver into place. Having the barrel nut extension mated to the Super Reaction Rod lugs and fixing the upper receiver
before torquing will remove any potential stress that could be placed on the index pin. This allows the armorer to place tremendous torque on the barrel nut. The Super Reaction Rod’s pre-loading system can also be removed to allow it to work just like a standard
Reaction Rod, which allows upper work to be performed in 360° both vertically, and horizontally."

https://geissele.com/media/files/Sup...structions.pdf

[ed308]

Aero Shell expensive? $6.95 on Amazon for 2 ozs. That amount will last years.

https://www.amazon.com/AEROSHELL-33M...4QPC72Y4S7HWFQ

[rickyrick]

I’ll have to look, but I believe the bevblock engages the charging handle channel as well.

And yes, lube up all the surfaces that the barrel nut comes in contact with.

[PPGMD]

Aero Shell expensive? $6.95 on Amazon for 2 ozs. That amount will last years.

That price is, almost $12 for 2 oz. You can buy a 14oz tube of it for $17 plus shipping or $24 on Amazon with prime shipping.

Also it was renamed to Aeroshell 64 to avoid confusion with Aeroshell 33.

[ed308]

Yes but, you don't get that convenient screw-on lid with that tube.

[PPGMD]

You can probably find something around the house. I've used clean pasta sauce jars and nut containers. If you have an REI near by, which being in DFW you do, you can get some Nalgene Polypropylene jars for a $1.

The other option is to buy the same containers those dudes are, they can be had pretty cheaply for about $1 each on Amazon or less if you shop at Uline.