Ridgeline Defense RD-15 LPR

Looks like nicely put-together piece, with some very nice features.

But I don't think I'll be shit-canning my Knight's LPR anytime soon though. That is maybe the best all around AR I've ever had.

MM
 
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The RDM4 will use the same attachment method for the hand guard as the LPR but it will attach to a steel barrel nut in a more traditional manner to allow for use on TDP spec upper receivers. The combination of attachment and barrel nut material reduces the amount POI shift from the hand guard interface fairly significantly (in the range of 0.1-0.2mils) compared to designs using lighter/less rigid materials for the barrel nuts and that attach via a “pinch lock” method, which typically demonstrate 0.3-0.5mils of POI and in some cases a whole 1.0mils shift while under nominal influence from shooters interacting with barricades or tripods.

In a nut shell the RDM4 is designed to get the most out of “basic” AR15 components by minimizing POI shifts from the hand guard and POA shifts if LAMs attached to said hand guard.

Current lengths are focused on 11.5”, 14.5”and 16” (basically the hand guard with come to just behind the muzzle device with 1/4 to 1/2 of play) and will be in Black and FDE, MLOK and the MLOK/Arca combo seen in the LPR hand guard.
Out of curiosity will this rail system be available for any standard upper? Also will there a version available for sr-25 pattern rifles? Thanks.
 
Anyone have issues with failure to feed? Just did the break in and had some issues pop up where the round didn't properly feed after 2-3 rounds and the bolt didn't stay open after the last round. I assume maybe it was the buffer. Any thoughts?

Shooting AAC 77g and badlands 77g used new PMAGs and ensured the rifle was well lubed. Thanks in advance

On the positive side, the shot groups were extremely tight. I can't wait to get this performing right and take it to my next competition.
 
Anyone have issues with failure to feed? Just did the break in and had some issues pop up where the round didn't properly feed after 2-3 rounds and the bolt didn't stay open after the last round. I assume maybe it was the buffer. Any thoughts?

Shooting AAC 77g and badlands 77g used new PMAGs and ensured the rifle was well lubed. Thanks in advance

On the positive side, the shot groups were extremely tight. I can't wait to get this performing right and take it to my next competition.
Are you using the weak aac ammo? Have you tried razor core or other full power ammo ?
 
Anyone have issues with failure to feed? Just did the break in and had some issues pop up where the round didn't properly feed after 2-3 rounds and the bolt didn't stay open after the last round. I assume maybe it was the buffer. Any thoughts?

Shooting AAC 77g and badlands 77g used new PMAGs and ensured the rifle was well lubed. Thanks in advance

On the positive side, the shot groups were extremely tight. I can't wait to get this performing right and take it to my next competition.
Make sure the gas block is well aligned. Could be off center and leaking.
 
Anyone have issues with failure to feed? Just did the break in and had some issues pop up where the round didn't properly feed after 2-3 rounds and the bolt didn't stay open after the last round. I assume maybe it was the buffer. Any thoughts?

Shooting AAC 77g and badlands 77g used new PMAGs and ensured the rifle was well lubed. Thanks in advance

On the positive side, the shot groups were extremely tight. I can't wait to get this performing right and take it to my next competition.
When doing a function check I'd always try to use a standard 3oz (H0) carbine buffer weight and standard strength spring. This way you can tune if from there if it runs a little hard (swap H0 for H1 or H2). If you are still short stroking with h0 you likely have an issue somewhere else (gas port too small, gas rings worn out on bolt, gas key is loose on carrier, gas block misaligned, gas tube not going into the upper far enough, too much friction inside of bolt carrier/upper, etc.).
 
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The gas block is keyed into the barrel for centering
Forgot about that with the rd15. Thought I had seen photos though of a few that were off center.

@elnino57 do you know if you have the Gen 1 BCG or the one that they swapped out? I think there was a bad batch from their supplier and the second ones had a different sized logo.

They swapped mine at their shop so I can take a photo next week when I'm home. Or shoot them an email with a pic of it.
 
@NHPiper. The gas block appears to be centered. Attached is a picture of the bolt. No clue if it is gen 1 or not. Let me know if you need a picture of the entire bolt.

I just ordered a lighter buffer and will see if that does the trick.

@BurtG Used a match grade 77g from Badlands Mentions and also used PMC 55g all with the same issue.
 

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@NHPiper. The gas block appears to be centered. Attached is a picture of the bolt. No clue if it is gen 1 or not. Let me know if you need a picture of the entire bolt.

I just ordered a lighter buffer and will see if that does the trick.

@BurtG Used a match grade 77g from Badlands Mentions and also used PMC 55g all with the same issue.
Pretty sure that’s the recalled bolt

Yes it is

IMG_7301.jpeg

IMG_7300.jpeg
 
Pretty sure that’s the recalled bolt

Yes it is

View attachment 8776540
View attachment 8776541
Yeah the shift occurred around midway through FDE. The simplest way to tell the logo.
View attachment 8619767
The Toolcraft BCG is the front one, larger logo and slightly lighter coloration. The Mircobest in the back has a smaller logo and has a slightly subdued coloration.

If anyone needs replacement gas-rings hit me up at [email protected] and get you going with Blake to send you new ones ASAP.

Edit: apparently it’s [email protected] sorry for the confusion.
Yep
 
@NHPiper. The gas block appears to be centered. Attached is a picture of the bolt. No clue if it is gen 1 or not. Let me know if you need a picture of the entire bolt.

I just ordered a lighter buffer and will see if that does the trick.

@BurtG Used a match grade 77g from Badlands Mentions and also used PMC 55g all with the same issue.
Like others have said, that's the recalled one. The Ridgeline guys are first class. I am sure if you contact them for an RMA they will get you squared away ASAP.

I am pretty sure I'm running an H2 but can't remember if it's in front of a G super duty or sprinco spring. It cycles 100% with either an RC2 or RC3, although the RC3 is noticeably softer shooting.