SLR tips, tricks and observations

This is the correct way.

How so? The buffer retainer isn't even in it's notch so the buffer tube spins when I try to tighten the castle nut. If I give the buffer tube one more spin the buffer retainer sits perfectly in it's notch, and does it's job preventing the buffer tube from spinning.

The buffer tube is a cheap one from TNA, maybe that's the problem?
 
You need to send that receiver back to MDI ASAP. They will replace it. Its supposed to have a the cutout for the charging handle latch. Yours is not the first to have that issue.
 
How so? The buffer retainer isn't even in it's notch so the buffer tube spins when I try to tighten the castle nut. If I give the buffer tube one more spin the buffer retainer sits perfectly in it's notch, and does it's job preventing the buffer tube from spinning.

The buffer tube is a cheap one from TNA, maybe that's the problem?

The buffer retainer pin is not what's supposed to stop the buffer tube from spinning. The receiver endplate should have a "tab" that fits into the groove along the bottom of the buffer tube's threaded portion. It's the endplate that stops the buffer tube from spinning.
 
How so? The buffer retainer isn't even in it's notch so the buffer tube spins when I try to tighten the castle nut. If I give the buffer tube one more spin the buffer retainer sits perfectly in it's notch, and does it's job preventing the buffer tube from spinning.

The buffer tube is a cheap one from TNA, maybe that's the problem?

The pin does not seat all the way in that notch. Its fine.
 
I had one of those cheap buffer tubes from TNA last year with that notch. I threw it in the garbage and got a real buffer tube. TNA has great service, but their cheap crap is cheap crap.
 
How so? The buffer retainer isn't even in it's notch so the buffer tube spins when I try to tighten the castle nut. If I give the buffer tube one more spin the buffer retainer sits perfectly in it's notch, and does it's job preventing the buffer tube from spinning.

The buffer tube is a cheap one from TNA, maybe that's the problem?

I didn’t want to ask that, but you do not require such a large notch in the tube for the detent. It only needs a portion of the threading to retain the detent and spring. As already posted the tube is held from spinning by the end plate and castle nut.
 
I had the opportunity to measure a new lower's bolt catch pin holes. As best as I can tell this units holes are .088-.089". A number of 3/32" pins measured .092" measured from the split side to the opposite side, and about .098" on the non split sides. Once I squeezed the pin shut and measured again, it was about .092"

In a fastener manual I have it shows a 3/32" pin as being a max. .0938" and min. .0928"
Recommended hole size is max. .0956" and min. .0938"

I think a combination of undersized holes and a lack of "meat" on these ears are a big contributor to causing these to split.

I measured a number of 3/32" pins from different sources and they were all virtually the same, including one from a new DPMS LPK.

It's not to big of a deal to emery a pin down, if you know ahead of time that it needs to be done.

Hope this helps.
 
I had the opportunity to measure a new lower's bolt catch pin holes. As best as I can tell this units holes are .088-.089". A number of 3/32" pins measured .092" measured from the split side to the opposite side, and about .098" on the non split sides. Once I squeezed the pin shut and measured again, it was about .092"

In a fastener manual I have it shows a 3/32" pin as being a max. .0938" and min. .0928"
Recommended hole size is max. .0956" and min. .0938"

I think a combination of undersized holes and a lack of "meat" on these ears are a big contributor to causing these to split.

I measured a number of 3/32" pins from different sources and they were all virtually the same, including one from a new DPMS LPK.

It's not to big of a deal to emery a pin down, if you know ahead of time that it needs to be done.

Hope this helps.

When I assembled an MDI SLR I sanded down the pin lightly with a rotary tool and abrasive head. It takes a bit of patience but youre barely removing any thickness. Just enough to tap her in smoothly.
 
Anyone install an Odin rail on their SLR? Everything else went together properly, although it was exceedingly tight and roll pins needed to be sanded. The only issue I am having is my Odin 15 inch rail. It came off the 224 Valkryie upper I built while waiting for the SLR, and worked great, and now I cant seem to mount it straight. The two piece barrel nut is centred and I shaved down the inside of the rail on the injection port side to clear the enlarged features of the SLR but as soon as I start to tighten the screws it pulls the rail off centre. Next steps will be installing a different rail to see if the problem is the receiver but thought I would see if anyone else had troubles with this rail and the SLR. Overall fit and finish is good. Receivers fit nice and tight so I hope this thing is me because it looks like a good piece of kit. Thanks.
 
If the barrel nut is squared, then I would think that the rail is pulling to one side (if that's what you are describing? Pulled to one side not rotated) because there is a gap between the nut and the rail. You could try tightening the screws by doing each one a little at a time across from each other, not just tighten one side first then another.

Is it pulling to the side that you ground down?
 
Anyone install an Odin rail on their SLR? Everything else went together properly, although it was exceedingly tight and roll pins needed to be sanded. The only issue I am having is my Odin 15 inch rail. It came off the 224 Valkryie upper I built while waiting for the SLR, and worked great, and now I cant seem to mount it straight. The two piece barrel nut is centred and I shaved down the inside of the rail on the injection port side to clear the enlarged features of the SLR but as soon as I start to tighten the screws it pulls the rail off centre. Next steps will be installing a different rail to see if the problem is the receiver but thought I would see if anyone else had troubles with this rail and the SLR. Overall fit and finish is good. Receivers fit nice and tight so I hope this thing is me because it looks like a good piece of kit. Thanks.

Maybe post a picture if you can.
I had no issues as you can see in my post on the first page of this thread. I also had a but of shaving to do on the inside of the rail where it meets the reciever.
I also used the supplied gas tube centering pin to ensure it was lined up straight
 
Assuming the AR 15 version is the same as the ar10 it should be pretty snug once you torque the second piece of the barrel nut. Leave the gas tube plug in, I'm surprised the rail is rotating that much.
 
Just curious to know the date you ordered vs the date it arrived?

I have everything to build mine bought, and have been like a child on the day before Christmas for months on end waiting for this puppy in the mail.

fyi, I ordered mine mid April 2018

Thank you everyone
 
Maybe post a picture if you can.
I had no issues as you can see in my post on the first page of this thread. I also had a but of shaving to do on the inside of the rail where it meets the reciever.
I also used the supplied gas tube centering pin to ensure it was lined up straight

Yup the pin is a must, and mine took a couple try’s before the pin didn’t bind up. I used a BEV block, not sure if that made a difference or not too.
 
A great NR Black rifle for the Canadian market and the more I shoot it the more impressed I become. Today was a beautiful day for shooting steel at 200 yards.

 
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A great NR Black rifle for the Canadian market and the more I shoot it the more impressed I become. Today was a beautiful day for shooting steel at 200 yards.

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nice build
 
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