REVIEW: LAR Grizzly OPS-4 Upper Receiver

[702Shooter]

I found a thread here from back in May where the OP was asking about these uppers. Rather than bumping an old thread, I thought I would start a new one.

This review is part of an ongoing series detailing the various components we included in our recent Precision Rifle build and raffle.

Additional photos and videos can be found along with the review at:
http://www.702shooter.com/product-reviews/review-lar-grizzly-ops4-upper-receiver/

http://www.702shooter.com/wp-content/uploads/2010/12/IMG_00011.jpg

[Heavy Metal]

What keeps the charging handle from unscrewing while in service?

[702Shooter]

What keeps the charging handle from unscrewing while in service?

Great question.

The threaded plug is flat on the bottom and butts up against the lower receiver. It can not turn when the two halves are together.

http://www.702shooter.com/wp-content/uploads/2010/12/IMG_0009.jpg

[Heavy Metal]

Not the plug, the handle on the side. What retains it? What makes it captive?

[dennisuello]

gas key is not staked. :ph34r:

[702Shooter]

Not the plug, the handle on the side. What retains it? What makes it captive?

Ah, my bad.

It has a hex head bolt inside. A drop of loctite and a firm turn with a hex wrench.

[702Shooter]

gas key is not staked. :ph34r:

2 reasons for that:

1: That's not the gas key that is on it now. This review is of the OPS-4 so the pics are of the OPS-4 BCG and gas key. We added a POF-USA Roller Cam Upgrade which replaced the gas key you see in the photos.

2: Staking is typically so you can not remove the gas key. A bit of loctite does the same job but not as permanently. We did not stake the gas key with the upgrade either because we gave this rifle away and the person who won it may want to reconfigure things.

[Heavy Metal]

Ah, my bad.

It has a hex head bolt inside. A drop of loctite and a firm turn with a hex wrench.

You are saying you loctite the threaded shaft into the bolt carrier? Or is there something else that captures it?

I think you are talking about the knob on the shaft being loc-tited aren't you.

I am wanting to know what keeps the handle from unscrewing from the bolt carrier while it is in service, I.E. moving back and forth. I.E. What keeps it from self-dissassembling?

[702Shooter]

You are saying you loctite the threaded shaft into the bolt carrier? Or is there something else that captures it?

I think you are talking about the knob on the shaft being loc-tited aren't you.

I am wanting to know what keeps the handle from unscrewing from the bolt carrier while it is in service, I.E. moving back and forth. I.E. What keeps it from self-dissassembling?

They say a picture is worth a thousand words.

I'm building this into a 6.8SPC. Got about another month wait on the barrel.

http://www.702shooter.com/wp-content/uploads/2010/12/CH01.jpg

http://www.702shooter.com/wp-content/uploads/2010/12/CH02.jpg

[dennisuello]

I think his point is that locktite in that application is not ideal, as the heat will render it nearly useless. But if you were to use high temp permanent locktite, how would you remove the bolt?

[702Shooter]

I think his point is that locktite in that application is not ideal, as the heat will render it nearly useless. But if you were to use high temp permanent locktite, how would you remove the bolt?

I've had a Y/M side charge upper for a few years. No loctite and it's never come loose.

[Heavy Metal]

I think his point is that locktite in that application is not ideal, as the heat will render it nearly useless. But if you were to use high temp permanent locktite, how would you remove the bolt?

If it were me, I would make it captive by making the root a big square that bears against the bottom of the opening and make it so it can only be unscrewed in its rearmost position when the recievers were open, I.E. in a location beyond the rearmost travel of the bolt carrier during a normal recoil stroke.

I would also make sure the engagement was generous enough that you could not curb-stomp it and strip the threads or bend the handle in any way, shape, manner or form.

I do find this concept intriguing (The right-side charger) but I am afraid is simply is not sufficiently robust for heavy-duty use in it's current incarnation.

A version with the above mods and an AR-18 type dust-cover would have potential for real-world, two-way range type use.

[nickdrak]

How do you remove the bolt if the side charging handle has loc-tite applied to it?

[702Shooter]

How do you remove the bolt if the side charging handle has loc-tite applied to it?

By using blue instead of red.

[702Shooter]

If it were me, I would make it captive by making the root a big square that bears against the bottom of the opening and make it so it can only be unscrewed in its rearmost position when the recievers were open, I.E. in a location beyond the rearmost travel of the bolt carrier during a normal recoil stroke.

I would also make sure the engagement was generous enough that you could not curb-stomp it and strip the threads or bend the handle in any way, shape, manner or form.

I do find this concept intriguing (The right-side charger) but I am afraid is simply is not sufficiently robust for heavy-duty use in it's current incarnation.

A version with the above mods and an AR-18 type dust-cover would have potential for real-world, two-way range type use.

Although I understand your points, I think you're way over thinking this. Can you curb stomp a standard AR charging handle and not screw it up? No, you can't. Does that mean it's not robust enough for heavy duty use too?

Get your hands on one of these and check it out for yourself. They are solid. I've been told that the Las Vegas Police ordered 300 LAR rifles with these uppers.

[Heavy Metal]

When the AR CH is fully in-battery? It would be hard to curb-stomp it.

Having to rely on an adhesive to keep a field-grade weapon servicable is simply unsat. That assembly needs to be captive and I can think of at least two ways to make it such. The first one I mentioned, the second one would be to more or less directly copy the Daewoo with a captive dovetail root.

The problem with the Daewoo solution is it would move the root of the CH to the top of the ejection port and move the handle closer to the accessory rail. The solution I proposed would require only a slightly larger hole at the end of the slot to allow rotation and a square root for the handle(and I would go ahead and use a larger diameter threaded portion(journal,shank, root, whatever you want to call it) while I was at it). This would also totally eliminate the need for any adhesives.

This is fine for a Three-Gun rig but a more robust solution is needed if you are going to market this to the two-way shooter crowd.

Loctite is fine for static assemblies but this is not a static assembly.

[702Shooter]

When the AR CH is fully in-battery? It would be hard to curb-stomp it.

Having to rely on an adhesive to keep a field-grade weapon servicable is simply unsat. That assembly needs to be captive and I can think of at least two ways to make it such. The first one I mentioned, the second one would be to more or less directly copy the Daewoo with a captive dovetail root.

The problem with the Daewoo solution is it would move the root of the CH to the top of the ejection port and move the handle closer to the accessory rail. The solution I proposed would require only a slightly larger hole at the end of the slot to allow rotation and a square root for the handle(and I would go ahead and use a larger diameter threaded portion(journal,shank, root, whatever you want to call it) while I was at it). This would also totally eliminate the need for any adhesives.

This is fine for a Three-Gun rig but a more robust solution is needed if you are going to market this to the two-way shooter crowd.

Loctite is fine for static assemblies but this is not a static assembly.

Contact the manufacturer. Maybe you can make some money off it.

http://www.largrizzly.com/web/guest/contactus

[Heavy Metal]

I did look at the videos on your website.

There is some good thinking in this. The dual-sided version does not interest me simply because it exposes too much area to the intrusion of debris. I like the sand cuts, however.

I think the idea has some potential but needs that extra 10% of attention to address some murphy-proofing issues in order to take it beyond the competetion arena.

[scottryan]

What is the point of all this?

[Sanpete]

I don't understand the point of the threaded plug. Why not just keep the standard charging handle in place there?

And staking a gas key has nothing to do with preventing purposeful removal. I think you know that.

You say the y/m is just modifying parts while this is much different from the ground up. I'm not seeing any significant differences. They appear to function exactly the same using the exact same knob and placement and receiver.

So you put loctite on the charging knob threads and tighten with a wrench. Now you get to carry a wrench a bottle of loctite with your rifle everywhere, anytime you want to simply service your rifle and remove the carrier (since that big knob otherwise prevents a simple removal). This is worlds different from pushing a takedown pin and simply pulling your normal charging handle to remove the carrier.

No different than other side chargers already on the market. I guess some think they're cool but I fail to see any practicality.

[Steve_Morrison]

2 reasons for that:

2: Staking is typically so you can not remove the gas key. A bit of loctite does the same job but not as permanently. We did not stake the gas key with the upgrade either because we gave this rifle away and the person who won it may want to reconfigure things.

I saw one of these complete guns in my shop earlier this week under evaluation for an LE agency. I think they are fine for casual use, but the sample we had here lacks some important details to be considered for serious applications.

Staking is done to keep the carrier key screws from backing out and maintain the seal between the key and the bolt carrier, which is pretty important in that it enables the gun to function correctly. The T&E rifle here was not staked.

[morbidbattlecry]

It looks pretty neat to me i might have to pick one up and try it out. I with the CH had a better way to be removed then screwed in. Have when you fire it how close does it get to your face when you shoot nose to CH?

[Magsz]

To the OP.

Why defend the product? Do you have anything invested in this or are your responses based on emotional attachment?

The simple FACT here is that a non staked gas key is sub par.

The bolt knob being held on by BLUE locktite which will break down via the heat of operation is also unsatisfactory.

Perhaps rockset would be a better alternative in that location but i would rather not have to apply a thread locking compound each and every time i decide to take down the gun.

As is, a current AR15 can be taken apart with nothing more than a bullet tip to fix element induced malfunctions such as a popped primer in your FCG.

This item can be taken apart but not put back in its "fighting" condition without the use of tools and threadlocking compound. This is a hobby gun and it might be an excellent hobby gun at that but trying to portray this as a fighting gun or a good quality self defense firearm is a losing battle. I am referring to your statement about Las Vegas PD and their supposed purchase of 300 rifles.

[Russ4777]

I did look at the videos on your website.

There is some good thinking in this. The dual-sided version does not interest me simply because it exposes too much area to the intrusion of debris. I like the sand cuts, however.

I think the idea has some potential but needs that extra 10% of attention to address some murphy-proofing issues in order to take it beyond the competetion arena.

I'm sure all your negative comments have value to someone out there. If you don't like the LAR OPS-4 then just move on.

[Heavy Metal]

I'm sure all your negative comments have value to someone out there. If you don't like the LAR OPS-4 then just move on.

If the best you can do is dredge up a two year old thread to make a utterly useless, snarky comment with zero content value for your second post on this forum, I suspect I will not be the one of us doing the moving on thing.

If my criticisms are not valid, then try explaining why instead of drive-by snark on a necropost. All you are doing is stirring up the beehive again.

Did I crap on your favorite upper or something? I am sorry if my calling it a gamer piece (and correctly so) failed to validate your purchase.

[Cessnacit]

Just found and purchased one of these uppers left side charging. I was very excited. It's my first build, but after looking at multiple examples mine is different in a few ways and was curious if it may be a fake, only example I could find was a 4991949919omega manufacturing, or is it just a variation early or late production. The areas of concern are starting with the right side of bcg, 4 holes plus one for charging handle all examples only had 2 plus charging handle hole, and shape of charging handle itself and of gas screw were charging handle would go are different. Also, has silver gas block screws instead of the normal black. Any information is appreciated thanks.

[Iraqgunz]

Nice. You have now secured a spot for Necropost 2018 Awards.


Just found and purchased one of these uppers left side charging. I was very excited. It's my first build, but after looking at multiple examples mine is different in a few ways and was curious if it may be a fake, only example I could find was a 4991949919omega manufacturing, or is it just a variation early or late production. The areas of concern are starting with the right side of bcg, 4 holes plus one for charging handle all examples only had 2 plus charging handle hole, and shape of charging handle itself and of gas screw were charging handle would go are different. Also, has silver gas block screws instead of the normal black. Any information is appreciated thanks.

[Cessnacit]

49920499214992249922

[26 Inf]

Nice. You have now secured a spot for Necropost 2018 Awards.

Third place.