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Discussion Starter #1 (Edited)
Just got mine Friday and pretty much have it together. Need to lap the bolt.

Did some checking and the right lug is at 80% contact and "zero" on the left. This was with two exc bolts and one NIW..all USGI. Left lug gap is less than 0.003 so I should be ok.

Just wondering if you are seeing the same when fitting your bolts?
 

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Lug contact has been solid with the two I've built so far. Test fit a rear sight. I had issues with windage clicks on number 66.
 

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interesting. my rockola had contact on both lugs off the bat. what you described is very common on lrb receivers. i lapped my bolt into my lrb receiver yesterday and had to lap a little off the right lug before the left started to contact, not a big deal if you have headspace to play with but it is a big deal if your left lug isnt contacting and your headspace is 1.635 or so, then you have a problem. it can be tricky to really get a feeling for what the lug contact is by using finger pressure alon. are you checking your contact with a barrel in place and a cartridge cut in half with a stout spring in it? that is the best way that i have found to check lug contact. post pics if you can
 

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Discussion Starter #6
Lug contact has been solid with the two I've built so far. Test fit a rear sight. I had issues with windage clicks on number 66.
Yup, brand new USGI NM windage knob will NOT tighten up enough to engage the clicks.

Barrel is in place with my lap spring/case in place with zero left lug contact....did this with three bolts.

Ser# 14X
 

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Yup, brand new USGI NM windage knob will NOT tighten up enough to engage the clicks.

Barrel is in place with my lap spring/case in place with zero left lug contact....did this with three bolts.

Ser# 14X


I called and talked to Mark about the windage problem. The hole for the windage drum on the receiver ear needs to be beveled out a bit. Basically there is a "step up" on the windage drums and it won't seat fully on the receiver ear.

It took about 60 seconds with a dremel and a diamond bit and now I have perfect windage adjustment.
 

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I called and talked to Mark about the windage problem. The hole for the windage drum on the receiver ear needs to be beveled out a bit. Basically there is a "step up" on the windage drums and it won't seat fully on the receiver ear.

It took about 60 seconds with a dremel and a diamond bit and now I have perfect windage adjustment.
Did he say if this would be something their QC/QA process would catch and correct prior to shipment.
 

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This shouldn't really be our responsibility. Brycom can you post some pics.
 

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Did he say if this would be something their QC/QA process would catch and correct prior to shipment.
He said he hadn't seen that problem but I told him that the hole needed to be beveled slightly. We ended up talking for about 15-20 minutes and he seems like he is always improving things on the receivers due to the fact that they are also building on them.

Here are the pics. 60 seconds with a dremel. It looks like hell because my jewelers files are packed away because we are moving in a week. Once I get moved and unpacked I clean it up and put some cold blue on it. I'm not to picky with this part because its covered up with the windage drum. I'm sure an oversized carbide drill bit would make it look a lot better but again, they are packed away.

After I did this the rear windage knob is nice and tight with positive clicks.






Here you can see that "step up" on the drum shaft that is towards the inside of the drum. I believe that is what was hitting the receiver.

 

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I have a few carbide bits. I'll have to check this out. I am on my way to my basement to fit the stock liner for number 66. Rest of it is finished.
 

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Would the steps on the drum cause excessive wear on the receiver because you cut through the hardened surface?
No not really. Just lube it and you'll be fine. Its not really a bearing surface (I don't even think it's supposed to touch) to begin with and even if it was, its not like you're constantly moving the windage all the time.
 

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For reference here is a USGI M1 receiver 1.6 million range.
Thank you brycom1. Much obliged for the pics.
+1

I'll echo Jason's comment. This shouldn't be something the end user should have to grapple with. If you're selling a mil-spec receiver shouldn't it be just that? This is something that should be addressed in future receivers shipped to their customers.

Also, I'd like to hear from those who've built on later receivers and see if items from Jon Wolfe's review have been corrected. The ones that come to mind are;

1) The location of where the barrel threads engage the barrel and the resulting timing.

And...

2) The safety bridge firing pin bevel is improperly cut and doesn't meet spec.

Can anyone confirm Jon's initial observation? has JRA made any attempts to correct or have a willingness to listen to the experience of their customer base?

I'm very interested in one, but would be more assured knowing observations like these are being corrected.
 

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+1

I'll echo Jason's comment. This shouldn't be something the end user should have to grapple with. If you're selling a mil-spec receiver shouldn't it be just that? This is something that should be addressed in future receivers shipped to their customers.

Also, I'd like to hear from those who've built on later receivers and see if items from Jon Wolfe's review have been corrected. The ones that come to mind are;

1) The location of where the barrel threads engage the barrel and the resulting timing.

And...

2) The safety bridge firing pin bevel is improperly cut and doesn't meet spec.

Can anyone confirm Jon's initial observation? has JRA made any attempts to correct or have a willingness to listen to the experience of their customer base?

I'm very interested in one, but would be more assured knowing observations like these are being corrected.
I was told the barrel timing has been moved to 29 degrees and they have increased the size of the firing pin relief ramp
 

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+1

I'll echo Jason's comment. This shouldn't be something the end user should have to grapple with. If you're selling a mil-spec receiver shouldn't it be just that? This is something that should be addressed in future receivers shipped to their customers.

Also, I'd like to hear from those who've built on later receivers and see if items from Jon Wolfe's review have been corrected. The ones that come to mind are;

1) The location of where the barrel threads engage the barrel and the resulting timing.

And...

2) The safety bridge firing pin bevel is improperly cut and doesn't meet spec.

Can anyone confirm Jon's initial observation? has JRA made any attempts to correct or have a willingness to listen to the experience of their customer base?

I'm very interested in one, but would be more assured knowing observations like these are being corrected.

When speaking to Mark he stated that he did INDEED CHANGE the barrel thread timing.

I've just sent him an email talking to him about the windage drum issue. We had spoken before on the phone about it, but I had not yet done the modification yet. I let him know that the modification did work and I included the picture of the M1 receiver bevel so he could replicate it.

When speaking to him he said that he was driving his guys nuts about everything being perfect. Obviously, there's a bit of a learning curve with these receivers and he indicated that they are making necessary adjustments as they are noticed. GI2

In my opinion he's making a fine receiver that is only going to get better.
 

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Thanks for the heads up about the windage drum bevel issue.
I checked my JRA receiver, and sure enough no bevel. Can not
get USGI windage knob to seat to proper depth, and thus
do not have positive clicks.

I am reluctant to take a dremel or diamond file to my
new in box receiver...
 
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