Would like it to be. Shooting suppressed with a Alaskan Ti and seems AGB is best way to get a smooth low recoil rifle
Ridgeline Defense RD-15 LPR
- Thread starter B4forever
- Start date
I used a really small fixed gas block and gassed the gun using a .071 BRTgas tube that I progressively opened up with jewellers bits. It was a pita but the best way in my mind. I had to thermally fit the gas block. It's not going anywhere. The gun is gassed perfectly, it's just a bit gassier than it needs to be to function dirty. And there's no grub screws or set screws to loosen or walk.
I didn't measure anything. I went through three gas blocks I had laying in the bench. I installed the gas block, handguard, pointed the upper at my face and looked at the clearance. Obviously they all clear sitting static. And then I shot the gun. When I got big groups, stringing, and flyers, I pulled the handguard and looked for impact marks, moved on to the next gas block. I don't know if a static measurement from the block to the handguard is going to be a conclusive guarantee. It just depends on how much an individual barrel whips when shooting. I think you just have to shoot it. I shot the gun a lot for about a month. Couple times a day figuring all this out.
Edit: just realized I read your question wrong. It was a BRT gas block.
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I find it interesting that a company can invest so much time in R&D and still have the gas block contacting the handguard. Like WTF guys no one just looked in there and said damn thats a little close...I have a feeling mine might have the same issue but haven't pulled it apart yet. Overall I kinda regret selling my JP upper to get this one.
My blem upper. Gas tube roll pin wasn’t driven in all the way and gas block practically touching the handguard while static. I know of two or three other dudes who had uppers RMA’ed because of overly canted gas blocks.
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In their defense, I'm not saying conclusively this is the case. It could be and that would explain two wildly different looking performances from what I'm showing vs what Black Max is showing. It could just be that he's just showing two good looking groups that aren't truly representative and it's the barrel that is inconsistent. And it could be that the WOA barrel I have is a freak and it's just objectively better than the Proof. I will say when I looked at the bore of the Proof through a Hawkeye, it didn't look like any Proof barrel I've ever had. The bore looked a lot rougher and had tooling marks. Overall, I think this gun has a very "industrial" flavor to it. It definitely meets the claims of submoa. No one is contesting that I don't think. It uses solid parts. A5 system. Springco buffer spring. Well spec'd BCG. Geisselle SSAE trigger. The Proof barrel has a fat contour that should resist flex and whip. Solid, heavy gas block, perfectly gassed for the way it comes out of RD. It would be a solid gun to issue an operational unit. Based on my experience.
For my purposes and money, I just wanted better accuracy.
I’m late the to party here but it’s awesome to see folks putting new ideas into the platform. The gas block interface has always bugged me as it seems like a great design for mass production with 1950s technology. Tapers and keyways make so much sense in an era where barrels are being profiled on CNC lathes with live tooling capabilities.
Same on the upper receiver extension. The original design was great for plastic clamshell handguards but every method for free-floating a rail is a band-aid. The Seekins/Aero Enhanced bolt-on system is similar to what’s shown here, using an externally threaded barrel but, and has been proven in the precision AR space for many years.
Same on the upper receiver extension. The original design was great for plastic clamshell handguards but every method for free-floating a rail is a band-aid. The Seekins/Aero Enhanced bolt-on system is similar to what’s shown here, using an externally threaded barrel but, and has been proven in the precision AR space for many years.
I put a JP SCS and Lo Mass BCG in mine. Then I gassed the rifle for those components, suppressed. It truly changes the multi phase AR recoil impulse to a single, almost bolt gun like short, fast recoil punch. It sounds the upper is under gassed for the lower. If you have the funds an SCS paired with a Lo mass BCG could sweeten that up for you.
That's exactly the route I was planning on going, I have a jp bolts and carries in other rifles and love the feel. Why do you say the upper is under gassed for the lower tho? Im running their recommended buffer and a geissele trigger. Just curious what you think might be the issue caused in the lower? I do agree it does seem under gassed.
Ya, I don't know. It acts under gassed from what you say. Hard to tell how the mix of components can act. Springco green spring? Got any excessive wear marks on the tail of the BCG and front lower gas tube? There could be other things at play.
One tip for your SCS. Obviously you don't need the buffer retaining pin for the SCS so that gets removed with an SCS. Stack quarters behind the SCS until it constantly pushes on the back of the BCG. This eliminated first round flyers for me. I guess the theory is BCG bounce occurs when loading the first round. Having the spring/ buffer constantly pushing on the BCG seems to even out the potentially inconsistent BCG pressure. This was the final modification I made that really tightened up groups in the WOA barrel.
^ this love my lmos scs Douglas ar. Think I put the scs in the ridgeline too made it much smoother
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That doesn't answer my question nor make any sense, "misfires" have nothing to do with the gas system.
The problem there is the RD15 is specifically designed for full reliability and low mass system have notoriously been known for stoppages once the platform becomes compromised with fouling.
But yes they do make for a smooth shooting rifle and if you're not using it for rifle training classes or anything that will have prolong run times without cleaning they are quite enjoyable.
was
i was just talking about the buffer / spring. But I may have put the G super 42 in the ridgeline. Need to check. A5 wouldn’t work with my lower
Metaphorically. Hence the quotations. But I should have worded that more clearly. Apologies.
Yes, I tried two .750 gas blocks that did not have enough clearance to not impact the inside of the handguard when shooting.
You talked about using 875 and 936 gas blocks a couple pages back and I've mentioned a couple times in this thread that the inner diameter of the handguard is pretty tight and you probably won't be able to use those. I'm happy to let others talk about what gas blocks they've used but until people start building on those kits, I'm probably the only person who swapped a barrel out so far.
Why's that?
Did it fail to cycle properly?
I've had issues with A5 Systems before but it was because I was running too heavy on the buffer. A5 System shouldn't be any different than standard Carbine Systems, you just need to do your due diligence.
Over the years I have amassed a plethora of buffers so when building a custom rifle I generally build my own rifle specific buffer to put it in the proper operation window, some a with JP SCS with the tuning springs and weights.
The think mine is coming in on the 13th, I'll go more into depth on the gas block requirements for others as well.
Just to clarify you're talking about .750 "Adjustable" gas blocks, Or did you step down to a .625?
And what .750 gas blocks did you try out?
Asking so if I have them on hand I can cross them off my list.
I tried a .750 Seekins Adjustable and a .750 Aero non-adjustable. I ended up with a BRT non-adjustable .750. I didn't shoot the Seekins, I could tell just looking at it, that it wasn't going to work. They have those nonsymmetrical banana shape at the top.
The JP lo profile ADJ would be interesting to try out. But you're also limited down at the bottom of the block as well. The traditional square bottomed blocks have a little more meat at the 6 0'clock to make room for grub screws threads.
I think most people on here will be running superlative arms gas blocks. They look pretty low profile, maybe a smidge wider in the adjustment area than something like a BCM. I ordered mine yesterday so I’ll be putting the uppers together when they arrive at my dealer. 10 day CA jail for the lowers.
I have that gas block under a geissele rail which seems similar in dimension to the RD rail. It clears the geissele MK16 just fine on my 11.5 but not sure if barrel whip on a 16" would be worse enough to make contact.
I think the seekins triangular shaped handguards on their semi-monolithics are fugly as hell and I like to make fun of JP for making round handguard tubes in 2026. But guess what problems you never have with either of those two handguards?
Yep designed for reliability but mine sure isn't. My PCSL match rifle with RCA Ti carrier at 4.9oz and unrivaled buffer has yet to give me the any issues Im having with the RD. I agree with a true duty rifle full mass is the way to go but still think the JP low mass would be plenty reliable even for field matches but again just my opinion and experience.
Jp's handguards are the worst part about their rifles...super fugly but that new semi mono upper they have now is probably more solid then anything else out. Id like to see a POI test done on one of those. The gas block clearance tho is excellent.
I plan on buying one eventually.
I think the JP LoMass system gets some of that bad rep because it's part of a three component system that can be adjusted and tuned. So it gets used by people who maybe don't make the best choices when tuning. They try to set the gas, buffer, and spring weights in the extreme. And I think any system that has a wide variety of adjustability can be easily misused. And it's not just the wide adjustability but it's also adjustable on both ends of the operating system. So far, in all the guns I've had JP guts in and two JP rifles, I have been able to make them very reliable. They are 3G rifles by trade and in that use the owners put way more rounds during a given match day(read: without cleaning) than a precision rifle use.
I like my sgt arms. But the slim RD15 is so much nicer in the hand. Kind of like the Fix and Side Chick
I’m working a shutdown right now, 7 12’s. When this shit show is over with I will shoot a 5x5 and post the results. I’m as curious as the rest of you.
I saw that post btw. I was kinda confused why your test was with two support mechanisms in what I'm guessing was likely the same place on the handguard vs front bipod, rear bipod which is typically where you see the flex. Rear bipod, bagged just in front of the magwell(PRS barricade style), and tripod seem to have the same POI in everyone's tests. It's the front of the handguard vs the rear of the handguard that shows the POI shift.
Not trying to be a confrontational dick. Just openly discussing it.
The lockup on the RD handguard is a couple orders of magnitude stronger and stiffer than the Aero Enhanced and Seekins semi-monolithic. I assembled the RD, the Aero Enhanced (with both the Aero and SOA) and an SP-10 builders within a couple of weeks of each other and the difference is pretty impressive.
You're good, the sandbag was actually in the middle closer to the the mag well. I didn't want the front pic rail touching the sandbag during recoil.
I mounted the rifle completely different as well, with bipods I pull the rifle into my shoulder and then lean in (LOADING). With the sandbag the rifle was just pulled into my shoulder and resting on the bag.
The issue I see more often than not is when people fire from, as you say PRS Barricade Positions just forward of the Magwell you obviously loose the forward support you'd normally have from a bipod requiring different fundamentals.
Most people train and zero their rifles proned out with a bipod in it's most forward position with a rear bag for support, confusing true POI shift from your rifle's components compared to when you have to manipulate the rifle in a foreign position outside their normal technique, your POI shifts yes, but it's NOT due to handguard flex as in (THIS SPECIFIC TROPIC) its your shooting position and fundamentals that have changed causing your POI shift.
As shown in the POI Shift specific thread which honestly this conversation should be in, the topic is about mitigating POI shift by finding the most rigid upper to handguard configuration.
If you want to find the mechanical difference in POI shift in regards to rigidity utilizes a ARCA Rail and a Atas Bipod.
Prone out and apply the same load as you normally would with the bipod in its most forward (A-FRAME/VERTICAL) "standard" position and shoot a couple groups, then put the bipod legs in the notch folding back towards you this will apply the highest amount of torque on the handguard.
After that fold the legs away from you pointing forward, and repeat those three positions up and down the arca rail.
It's easy to get lost in the difference between mechanical POI shift and the POI shift you'll induce by changing shooting position which you can control by training and learning how to adapt your fundamentals to best suit your required shooting position.
I totally agree ref. the unintended POI/ basic zero shift induced by a shooter changing his inputs via natural point of aim and support. I've made that argument before. I don't think it's possible to drive a gun the same way, proned out vs off a barricade BUT... I have shot that test with a bolt gun and despite using different positional inputs was able to maintain the same level of accuracy and precision. So same zero and POI. So the positional inputs varued but I was still able to maintain the same POI. So if someone shoots a gas gun with the same POI and zero across all positions then shooter inputs apparently isn't a factor. But a very simple test would be far bipod vs near bipod, prone because those two positions should have identical shooter inputs. So when you see a shift there, you have a pretty good idea it's handguard flex.
No thats not what a said, shooter input is absolutely Paramount in regards to your fundamentals that are required in each shooting position. When you shoot from a position that has almost zero support to the front of your rifle mostly likely your POI/ACCURACY changes but only due to total loss of forward stability.
You adjustable your fundamentals to maintain your Zeroed POI in every position, so yeah shooter input is absolutely critical to achieve consistent zeroed POI with your DOPE.
If that's what you mean by shooter input.
