XCR first impressions

[rsilvers]

JustI got an XCR. I was originally going to order one with a 1:7 twist light barrel, but it was quoted as a 12 week wait. Instead saw one in a store with a 1:9 heavy, standard stock -- so got it. I hope to shoot 1000 rounds today suppressed side by side with an AR, and see which goes further. I will also add my impressions. My concerns so far, before shooting it, are:

1. Engraving on gas system extremely hard to see.

2. Ejector uses bolts. This is not really good practice on a firearm.

3. Bolt hold-open mechanism uses a small pin. Looks like a failure point.

4. Bolt hold-open lever uses a hex-head screw. This might fall out.

5. Trigger spring is chrome plated. I have never seen this kind of spring in a gun before and it makes me wonder what kind of spring wire it is.

6. Barrel is held in by one hex-screw. I would think two would be the way to go.

Otherwise, the basic design of the rifle seems outstanding all the way from the ergonomics to the mechanism to the 3-lugged bolt face.

Today I shot it and have some real experience:

XCR with 1:9 twist 16 inch heavy barrel, KAC M4-QD silencer.

During test, KAC rail panels would slide off. This is because the rail does not have the index points of the KAC, Daniel Defense, or some other military-adopted rails.

Rail has center milled out. This prevents it from being within Picatinny 1913 specs. Several accessories will not properly mount, including the KAC SOPMOD vertical grip.

Suppressed pretty well but I will sound meter it to be sure. I would like to either get a light barrel, or shorter or flute this one. I may weld on a silencer with an 11 inch barrel.

The gas piston tube was crushed on one side of the cutout when I got the rifle from the dealer. After shooting, the other side of the cutout was crushed also.

Seems to be hitting the upper.

Gas knob seems like a nice mechanism. Mine is almost impossible to read. The smallest hole was 0.042, which was still too larger for a KAC SOPMOD silencer. Brass was ejecting about 30 feet with M955 ammo.

I am concerned about the bolt hold-open pin on the left. It seems like it could be beefier. I don't think this would pass a military trial without that part being redesigned.

Bolt release is held in place by hex-screw. This may be ok, but it would seem a pin should be used.

Ejector is held in place by two bolts. These should be rivets if one caliber could be decided on. They should come factory drilled for safety wire.

Planned to shoot 1000 rounds today. At about 780 rounds I noticed that the barrel had come lose and shooting was terminated for the day. Before shooting, I made sure this bolt was very tight. A single bolt is not acceptable. The FN SCAR has four bolts and they have a secondary retaining mechanism. This needs two bolts, and they should have a spring-loaded ratchet which prevents rotation. I will have to safety wire this one for now.

Gas block held in place by a single set screw. This should have two taper pins from the side.

Until the barrel screw backed out, the shooting was great. It was very reliable up until that point. The gas block would benefit from white letters and maybe a larger diameter dial so that it is easier to see and turn.

The standard folding stock worked well. The controls were nice. I like the bolt release and selector.

 

[P.B.Walsh]

Wow, I would expect more from that kind of gun.

 

[Domino]

Nice review, I have always lusted over one of those and its intersting to hear someone look at their new gun objectively rather than "hey check out my Uber cool rifle that totally rocks!"

It sounds like you should work for the Robarm R&D team to make the weapon even better.

 

[KellyTTE]

And best of all, there's some gal that does all there 'tech support' and smithing that's obviously not a very accomplished shooter. I don't see the fascination for the XCR at all, the quality issues aide, the fact that SO many of their owners have problems is what the po-leece call a 'clue'.

/hides from the Robinson apologists

 

[everallm]

My question is why you bought the XCR since the majority of your concerns relate to the explict design features you must have been aware of?

Specifically that the XCR is a rifle that has been designed to from the ground up to allow caliber changes, barrel changes, user upgrades etc using only the tools you can pick up at a gas station.

Ejector uses bolts. This is not really good practice on a firearm

The ejector is bolted on as it is designed to be quickly and easily removed when changing between calibers. The bolts are secured using Loctite Blue

Bolt hold-open mechanism uses a small pin. Looks like a failure point.

There have been no reports of this occuring in the weapon.

Bolt hold-open lever uses a hex-head screw. This might fall out

There are no reports of this ever occurring and the bolt is secured in place using Locktite Blue

Trigger spring is chrome plated. I have never seen this kind of spring in a gun before and it makes me wonder what kind of spring wire it is

Trigger spring is stainless steel

Barrel is held in by one hex-screw. I would think two would be the way to go

See "The weapon has been designed to....."

Gas block held in place by a single set screw. This should have two taper pins from the side

See "The weapon has been designed to......" and "the bolt is secured in place using..."

As a consumer, if you don't like the product ans its design, sell it, in the current economic climate you should have no problems

 

[stubbicatt]

Well. Thanks for the writeup. I've been thinking of purchasing one. I think I will pass. The gas tube issue and the barrel coming unscrewed are unacceptable. The remaining issues don't really bother me all that terribly much, however.

Thanks for documenting and photographing these trouble points.

Excellent posting.

 

[RugerOldArmy]

Good objective review.

 

[rsilvers]

My question is why you bought the XCR since the majority of your concerns relate to the explict design features you must have been aware of?
I liked the layout of the rifle. I love my m96 and wanted to have an example of this rifle now in case I could not get one later. It is an impressive effort from an independent designer. Yes, I was aware of these points of concern before buying the rifle. I am happy I bought the rifle for why I wanted it and plan to keep using it. I am voicing my concern because I want it to improve.

Ejector uses bolts. This is not really good practice on a firearm
The ejector is bolted on as it is designed to be quickly and easily removed when changing between calibers. The bolts are secured using Loctite Blue
I know why they did it. And maybe there is no alternative if you want the ability to change calibers. Caliber changes introduce compromises and it may or may not be worth it for any given user.

Bolt hold-open mechanism uses a small pin. Looks like a failure point.
There have been no reports of this occuring in the weapon.
They should jut make the part one piece, and beefier, like an FAL bolt hold-open.

Bolt hold-open lever uses a hex-head screw. This might fall out
There are no reports of this ever occurring and the bolt is secured in place using Locktite Blue
This may be ok. Pins are still better practice and for a reason.

Barrel is held in by one hex-screw. I would think two would be the way to go
See "The weapon has been designed to....."
The FN SCAR has four bolts, and a secondary mechanism to keep them from backing out. One is not enough. Two might be. In either case, something needs to keep them from spinning besides torque stressing the thread.

Gas block held in place by a single set screw. This should have two taper pins from the side
See "The weapon has been designed to......" and "the bolt is secured in place using..."
One does not need to be able to quickly replace the gas block on the barrel. You can have one gas block per barrel. Two taper pins are needed before it would have a real chance in the military.

 

[flyboy1788]

Nice review. Interesting

 

[Reid73]

The gas piston tube was crushed on one side of the cutout when I got the rifle from the dealer. After shooting, the other side of the cutout was crushed also.

My unsolicited advice: stop hanging on to the magazine with your left hand while firing. Just ask anyone with experience of the Sterling what can happen when you do that. Muzzle control is poor, too.

 

[ny32182]

The ejector is *not* changed out during a caliber swap. Only the barrel/gasblock/gas valve assembly, bolt, and sometimes brass deflector.

 

[Coronach]

How hot do the parts "secured" via loctite get during firing? Loctite's strength is reduced with heat (heating the part is one of the steps for removing the loctited part if it is too stubborn to go by hand).

Anyone can make a lemon. Robarm seems to have made some, judging by other reports on teh intartube. However, what's not clear is the rate at which the guns have failed. Formal range reports aside, you're going to hear the gripes only, not the praises to the guns that run fine.

Mike

 

[Dr. Tad Hussein Winslow]

Nice review, I have always lusted over one of those and its intersting to hear someone look at their new gun objectively rather than "hey check out my Uber cool rifle that totally rocks!"

It sounds like you should work for the Robarm R&D team to make the weapon even better.

Yep, +1. Now that's how you do a review, boys & girls; thanks.

 

[maskedman504]

I have been considering an XCR for a while- the issues that worry me:

The gas block- can someone explain the damage there?

The barrel unscrewing is a very worrisome problem.

 

[ny32182]

The gasblock bolt and the barrel bolt are the only two that should be subjected to heat. Loctite is normally not applied to either of those to the best of my knowledge. The friction between the barrel bolt and its threading is substantial. I have never touched my gas block bolt, so can't comment on that one.

 

[ny32182]

If you mean the damage to the gas tube, no, I don't think anyone has an explaination for that one yet. It does not contact any moving parts, and has some slight fore/aft play when everything is properly seated. It is possible to install it with the index slightly off. That would be my only guess as to where to start.

 

[rsilvers]

The ejector should be rivited.

 

[ny32182]

Since it does not have to be removed, I agree, I think it would be an improvement. And it would be an easy retrofit to existing rifles. A sufficiently industrious individual could probably do it themselves?

That said, I don't consider the existing setup to be a major liability. The area is not subjected to heat, and it is twin bolts holding on a tiny little piece of metal. Once torqued and locktited, there are not really any reports of it working loose.

Of everything on the rifle, the barrel bolt is my biggest concern. Part of that is because an improvement, if ever deemed necessary, would probably entail a significant design change to the upper to add a second bolt and/or some sort of locking mechanism. Also since the area is subjected to heat, I presume locktite is not a good idea.

The friction fit on mine is quite snug and I have not had a problem, but truth be told I have not beat on it as hard as you did. I hope to be able to do so at a class someday. There are plenty of folks on XCRforum that have.

In the case outlined above, I wonder if the weight of the full heavy barrel combined with the weight of the suppressor could have been a factor.

 

[variablebinary]

Engraving on gas system extremely hard to see.

(Get another one. Terra will replace it for free.)

Ejector uses bolts. This is not really good practice on a firearm.

(If you want the bolts to stay in there, they will stay in there. I removed mine, cleaned the threads and bolt, applied red loctite, and torqued them to spec. Issues: 0. The internals get very little heat. You can place the BCG in your bare hand after full auto fire. Its very cool on the inside due to the piston)

Bolt hold-open mechanism uses a small pin. Looks like a failure point.

(Agreed. They changed the metals a bit to beef up the design since then, however, its not ideal. Its being redesigned into a single piece design, similar to the AR15)

Bolt hold-open lever uses a hex-head screw. This might fall out.

(Unheard of. Never going to happen unless you mess with it. Non-issue)

Trigger spring is chrome plated. I have never seen this kind of spring in a gun before and it makes me wonder what kind of spring wire it is.

(Not sure of relevance)

Barrel is held in by one hex-screw. I would think two would be the way to go.

(Torque it to 250lbs and report back. Make sure the bolt threads are clean)

During test, KAC rail panels would slide off.

(So don't use KAC panels. Do you see KAC panels on the FN SCAR or HK416?)

Several accessories will not properly mount, including the KAC SOPMOD vertical grip

.
(Really? What accessories were you thinking? I use a TD and Larue VFG personally. The KAC VFG is a relic from a decade ago so I could care less. Name another device that's a problem.)

Suppressed pretty well but I will sound meter it to be sure. I would like to either get a light barrel, or shorter or flute this one. I may weld on a silencer with an 11 inch barrel.

(Since you do suppressors for a living, I've always been curious about the effects of suppressor on a 16” pencil barrel. The XCR light barrel is very thin. I also would like to know how quiet the XCR is as well. I am torn between a Gemtech and AAC Can. Also, how will AAC products work with Robinsons 9" PDW barrel)

The gas piston tube was crushed on one side of the cutout when I got the rifle from the dealer. After shooting, the other side of the cutout was crushed also.

(This is bizarre. My first XCR ate 10,000 rounds and the gas tube had no dents. Nothing hits the gas tube. It just sits, floating between the gas block and upper receiver, while the op-rod moves inside of it. The gas tube has about 1 millimeter of back and forth play, but it isn't subjected to enough blunt force to dent it by any means. Get it replaced and refer to the manual when you install it)

Gas block held in place by a single set screw. This should have two taper pins from the side.

(I dont see how that could hurt. Never heard of anyone having an issue however.)

 

[rsilvers]

KAC panels -- not a big deal. It is not in the 1913 spec anyway. It is by a vast margin the most common rail panel though so it would not hurt to accept them. Most rails in existence accept them. I believe Daniel Defense rails accept them. It is a feature but not a required one. I am not even sure if I would do it if I was in charge of the rail.

The 1913 standard requires the center of the rail to be present. That is required. Military will not accept without it.

I am not concerned about the pencil barrel with a suppressor.

 

[Dan Crocker]

My unsolicited advice: stop hanging on to the magazine with your left hand while firing. Just ask anyone with experience of the Sterling what can happen when you do that. Muzzle control is poor, too.

I'm curious, why is that a bad idea? I've been doing in that way for years because it (again, for me) locks things in tighter and I don't feel like I'm muscling the gun up on a point way out in front of my body. What was it about the Sterling (are you talking about the SMG?) that made that a bad idea?

 

[rsilvers]

I think because if you have a case rupture you can burn your hand. I did once have an AR blow out and the magazine floor plate blew apart. I would not have wanted to be holding it when that happened.

 

[stubbicatt]

If everything else were rectified, I still think the barrel bolt backing out is a definite "no go."

Yeesh. I think this rifle is probably pretty good as a hobbyist, or plinking type rifle, and it shows initiative of RA to produce it. I don't think it is a serious weapon tho, based on this review.

Thanks RSilver for your efforts in documenting your discoveries.

In favor of RA, it is difficult to idot-proof a rifle, as idiots are so resourceful...

 

[FlyinBryan]

im totally stumped by this review.

you have reviewed the rifle like it was someone elses gun, which like was said above, is not what im used to seeing.


it was graded without ego as a factor.

i probably would have never bought one anyway.

they never really tickled my fancy

 

[ny32182]

Every rifle out there has a "major deficency" folks. I agree that rsilvers' review was a good, quality non-biased presentation of his impressions and results of one extended shooting session. If he did the same with any rifle on the market, it will show something that you don't like, as nothing is perfect. You have to learn to live within the limitations of any rifle, and yes, even the XCR has things here and there that could likely be improved upon.