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Hello all,
I would like to replace the barrel bolt with a bolt with no head at all, Would that work? I'm not sure if it hold the barrel to the receiver the way it was made to. I think it would tighten up on the barrel and not on the receiver. I'm not sure if that would be good or not.
I know I could use a round head bolt but could I use a headless one?
thanks for any info.
 

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I have one on mine,Bravo turned me onto it.You can use a set screw but it has to be a certain type,I'll look for the thread and post the link.

http://xcrforum.com/index.php/topic,2415.0.html

This isn't the first place where this has come up,but it's a good start.
 

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I recall Bravo saying he had to order them by the bag so he had several extra. This was awhile back but you could try asking him. On a side note I turned down a standard bolt to work. Figured I could find some kind of wrench or suitable substitute just about anywhere in an emergency instead of trying to find a hex key.
 

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PM Bravo, he may still have some. If not you can go anywhere that they sell bolts and purchase a hex set screw that would work. You would just need to insure that you the pointed portion of the new screw matches the same angle of the original bolt.
 

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I replaced mine with a set screw from a local hardware store. It's a 5/16-18x1/2, but it's a little short and it sits a bit recessed in the receiver (still better than the original cap screw). A 5/16-18x11/16 would be perfect. I've tired online but haven't found one yet. Anyone know of a source?

 

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Roughneck-2zero, Although 11/16 would be flush, it is not a standard thread length. We have found 5/8" to be ideal. It has full thread engagement with the helicoil insert and is almost flush.

If you see my post below, you can see the size and part number.
http://xcrforum.com/index.php/topic,2415.msg39102.html#msg39102

The "MSC" is found here...www.mscdirect.com You can also check out www.mcmastercarr.com
As mentioned, you will need to buy a quantity of 100 from those sources.
Some hardware stores may carry the desired size.
I bought mine from http://www.gsfasteners.com/bolts.htm It is very close to my work. They sell them individually.

Hope this helps.
 

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Thanks. I've ordered set screws from a few different places in 5/8 & 3/4 lengths. I'll post the results (with pics). I found something called a "button head bolt". They're like a pan head but have a hex drive hole. These would have been a better choice from the factory.

I did have to order [email protected]/8" long set screws. Obviously I wont need that many. If they are gtg, I'll sell the rest cheap. Probly just .50 to cover an envelope & stamp. ;)
 

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All right. I tried a button-head bolt, pan-head bolt, 3/4 set-screw, and 5/8 set-screw.
The 5/8 is perfect (now I have 99 more of em in a bag). Now I have no interference with my lights' thumb-button. Besides, the same allen wrench fits the barrel screw & the Gas-block screw.

BTW, all of the bolts I found are SS, and for some reason they really bind up when I tried to use them. ???



 

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All right. I tried a button-head bolt, pan-head bolt, 3/4 set-screw, and 5/8 set-screw.
The 5/8 is perfect (now I have 99 more of em in a bag). Now I have no interference with my light button. Besides, the same allen wrench fits the barrel screw & the Gas-block screw.

BTW, all of the bolts I found are SS, and for some reason they really bind up when I tried to use them. ???


They bind b/c stainless helicoils with stainless screws are a disaster waiting to happen.

I'd HIGHLY recommend you find some zinc coated or even a standard "black oxide" coating instead.

I work in the aircraft industry and galled threads from using SS screws with SS helicoils is common and a giant PITA.

HTH,
Sean
 

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They bind b/c stainless helicoils with stainless screws are a disaster waiting to happen.

Good to know!


Roughneck, that's a snazzy looking rifle there! Black rifles are so last week. :D
 

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They bind b/c stainless helicoils with stainless screws are a disaster waiting to happen.
Yep,it's called galling,same reason you should never use stainless brushes in a stainless barrel.
 

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If by lubed you mean cleaning solution,I can't say If it would or not,but I wouldn't take the chance.
 

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Ohhh ok. Thats good to know. I didn't put too much pressure on em when they started binding up, I knew something was wrong. The set screws I ended up using are steel with black-oxide finish.

Bazooka; Hey, if you want this type of set screw I have 99 more, I can send you a couple.

m118sb; Thanks, I got into duracoating awhile back and went kinda overboard. I dont' have a black firearm any more (well my shotguns are still black). I know this is a post about the barrel bolt but I can't help posting a pic of some of my tools.


The Sig is factory camo. I duracoated the Glock & Baretta (and even the gun case, dam).
 

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Update: The company I found is awsome. It's called McMaster-Carr, Inc. their website is www.mcmaster.com
They have so much stuff, not just nut/bolts, but tools, equipment and the list goes on. Their site is very easy to navigate through, I went to fastners, set screws, picked out the style, material, finish, size and got exactly what I wanted. I did have to order a pack of 50 ($13.50), but that pretty normal.
 

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I just ordered from the same vendor, and probably the same set screw:

Screw Style Standard Socket
Material Type Steel
Finish Black-Finish
Point Flat
System of Measurement Inch
Inch Thread Size 5/16"-18
Decimal Equivalent .312"
Hex Size 5/32"
Length 5/8"
Thread Fit Class 3A
Rockwell Hardness Minimum C45



 

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FWIW, I tried some that appear to be identical to the one in the pic.

I like the full conical slightly better - you can take down a SMALL touch from the tip of the cone, and it gives you more engagement surface.

FWIW
 

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I didn't have any problems specifically with it, I just didn't like the limited bearing surface area and went with something 'with more'.

But I didn't run that one enough to really say if it'd work well in the long-term or not.

I didn't get the conicals from McMaster, but it does appear that the one you linked is the same (or at least enough so that I can't tell the difference) as what I have.

With the conicals, about four seconds on the grinder will take off the tip of the cone. Just take off enough that it doesn't get into the threads of the barrel (through the barrel extension all the way).

So far, with the conicals, I've had nothing but great success. Over 5K on my first XCR, and I'll hit 5K (or should anyway) on my second XCR this summer.

The only thing I'd change - if I could - would be the length. The conicals are slightly (SLIGHTLY) too short. You can see a tiny bit of a helicoil. Won't hurt anything structurally, but I just prefer to have the threads hidden (GRIN)

FWIW, I do just like Terra said: keep a torque wrench handy, set at 250 inch pounds. Works great.

Also, these screws take the same hex drive that the gas block screw does........ very convenient!
 

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Thanks, Bravo.
Very useful info.
I got my bolts today (cup end). Going to shoot it tonight. The rifle is sure more comfortable to hold now (an understatement).
But now you got me thinking about "more surface", chances are I will order the cone.
Cannot be too anal with my XCR, can I?
 
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