Bolton gas block & Ultimak rail... doh!

[AshWilliams]

I know there's a wealth of knowledge on this board so here goes:

I recently sent my Bulgarian Arsenal off to get some custom work done and I noticed something I thought peculiar on the front end. The Ultimak rail fits completely snug around the Bolton gas block. Having installed an Ultimak rail on a WASR-10 myself, I installed it so that the Ultimak rail fits loosely as per the instructions so that it accounts for the flexing of the rifle during discharge. I searched the interwebs and found pictures where snugness is the case and others where it is not.

So my questions are: Has anyone else seen or experienced this with Arsenal rifles and Bolton gas blocks and Ultimaks? Will this negatively affect the rifle in any way? Am I fixating on this and letting my OCD run amok?

I'm attaching pictures and I'm looking forward to any insight you guys and gals can give me. As always, it's greatly appreciated.

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[Boboclown]

Fit it*. It gets hot, expands, puts more pressure on gas block, and thus affects zero. In theory anyways, but likely to happen.

Reasons like that are why I just use a siderail or zenitco.

*Time to file it or something.

 

[AshWilliams]

Fit it*. It gets hot, expands, puts more pressure on gas block, and thus affects zero. In theory anyways, but likely to happen.

Reasons like that are why I just use a siderail or zenitco.

*Time to file it or something.

Thanks man. So you're saying file down the end nearest the new gas block? That makes sense, but judging by how tight it looks it might be tough to get off of there, but I suppose it shouldn't be too much trouble. I guess I'm just disappointed that the shop didn't fit it, you know, especially if I'm paying for that service. Anywho...

 

[Boboclown]

Thanks man. So you're saying file down the end nearest the new gas block? That makes sense, but judging by how tight it looks it might be tough to get off of there, but I suppose it shouldn't be too much trouble. I guess I'm just disappointed that the shop didn't fit it, you know, especially if I'm paying for that service. Anywho...

It shouldn't touch rear sight base or gas block. Both are on the barrel, so pressure from ultimak will affect things.

 

[titsonritz]

It is a non-issue. Here is what Jim Fuller says on the subject. Go to the 3 min mark...
Question 3

 

[Boboclown]

What Jim Fuller is saying, and much like the Files I don't take much creedence to what he says, is different from the OP's situation where the ultimak is fitting snuggly between both rear sight base and gas block.

Whereas Fuller is talking about the Ultimak still being "loose" between the two parts, but moving it forward to touch the gas block anyways.

 

[Boboclown]

Unless its only touching the gas block and the OP confused me.

Either way, no real reason for it to touch the gas block.

 

[AshWilliams]

Guys, thanks so much for your replies. This is indeed from Mr. Fuller's shop, so that video response was exactly what I was looking for. I will check the rifle's rear site base again when I get a minute and report back.

Cheers!

 

[Boboclown]

If there's a gap at the rear sight base then I'd move it back. Might as well do it the way Ultimak says to.

The gas tube is there to guide the piston. Most of the work is done in the gas block. Here's a video of an even shorter Ultimak mount being used, and the AK still cycling.

UltiMAK AK Gas Tube Optic Mount-- Too Short?

 

[AshWilliams]

Unless I'm misunderstanding, this looks to be installed exactly as stated in Jim Fuller's Q&A response video: it's mounted all the way forward and flush against the gas block with some room at the rear sight base.

Let me know if you see it differently based on this picture.

Anyway, thanks again for the feedback all.

Cheers!

 

[Boboclown]

Its the way Fuller said on his video. His reasoning for doing it is BS to be honest. You don't need MORE gas to push the piston, especially with a suppressor that'd make an overgassed gun even more overgassed. Most of the work is done in the gas block anyways, the tube is just a guide.

Its not going to affect function but given that things expand and contract with temperature it would look like vertical stringing would happen earlier.