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Old July 2, 2020, 01:56 PM   #1
mel80
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Second 6.5 grendel build is officially on! 28" ELR build

specs so far
custom 1-8T 28inch stainless hbar +2 gas system .936 at the gas block (McGowen barrel) threaded 5/8-24
titan brake/qd adapter for the 7 inch titanium can
20inch slim mlok handguard
.936 micro gas block
NBS Slick side rear charging billet reciver
Nightforce nxs 5.5-22 X 56 scope
Luth ar mba-1 buttstock ( may change )

not sure on bcg/buffer combo just yet , im going to try out a few of the options i already have on hand i may opt for a low mass bcg

for now its going on a dpms panther lower receiver till i find one i like

still on the hunt for the lightest trigger i can find

parts should start rolling in sometime next week ill post pics as they come in except for barrel thats 8-10 weeks out
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Old July 17, 2020, 03:27 PM   #2
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Some parts starting to roll in finally
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Old July 18, 2020, 08:25 PM   #3
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I am almost done with my 6.5 Grendel build. It started on a whim when I found a 20" 1-8" twist stainless barrel on sale at the same time a local FFL had new Noreen lowers on sale for $50.

I'm running the Luth MBA-1 stock as I want the adjustments that it offers. I am also going to run my AAC M4-2000 suppressor. AIM had a sale a while back on a single stage adjustable trigger and I decided to use it on this rifle along with an adjustable gas block. It's already assembled, I'm just waiting for a few parts to show up to put the finishing touches on it.
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Old July 18, 2020, 08:35 PM   #4
mel80
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nice my other grendel is a 20 and ive been doing alot of long range stuff with it 1850y so far that about the limit with it though . the 8+ week wait on my new barrel for this build is killing me though , rest of my parts for the build except for a trigger will be here next week hopefully . . almost got my hands on a high speed national match trigger for a good price , but thinking i may just find the lightest single stage trigger i can find instead since im usied to single stage triggers
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Old August 10, 2020, 09:29 PM   #5
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getting there , just waiting on mcgowen to finish the barrel
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Old August 13, 2020, 12:11 PM   #6
Tallest
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The below is an excerpt from something Criterion Barrels put out recently. While I'm not an expert, this made a lot of sense to me.

Quote:
There is a wide range of parts directed towards the AR-15 market that promise to make your rifle run smoother, flatter, more reliably, and produce better accuracy... Many manufacturers either don’t have a thorough understanding of the AR’s 8-step cycle of operation or prey on customers lack of knowledge and understanding of what makes these rifles perform. Lightweight and skeletonized bolt carrier groups reduce lock time which decreases accuracy and reliability while increasing wear and tear on internal parts and components like your extractor, lugs, bolt, cam pin, chamber walls, etc. Lightweight components negatively affect the timing of your rifles 8-step cycle of operation. If one part is changed, it is generally recommended to change other parts to make up for the effects of the “specialty” part... this is where an in-depth understanding of the rifles operating system is required and where many rifle builders run into issues.
I am by no means attempting to qualify your level of expertise or tell you what you should or should not do. But this drew me up short when I was on the same BCG path you mentioned, and as such, I thought it may be helpful. YMMV
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Old August 13, 2020, 02:27 PM   #7
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Quote:
Lightweight components negatively affect the timing of your rifles 8-step cycle of operation.
I did get a chuckle out of my friends choice to use a lightweight BCG in a 6.8 build. Ended up using the heaviest buffer he could to tame down the brass from flying downrange. In the end the rifle weighed about the same and he spent more $ for a lightweight BCG and a heavier buffer. I'll stick with my mil-spec stuff, it's nothing to brag about but it gets the job done.
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Old August 13, 2020, 02:40 PM   #8
mel80
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im not going to buy one till i see how it behaves with my std bcg's with the +2 gas system and adjustable block it may be of a benefit on this rifle
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Old August 13, 2020, 02:54 PM   #9
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Quote:
Originally Posted by mel80 View Post
im not going to buy one till i see how it behaves with my std bcg's with the +2 gas system and adjustable block it may be of a benefit on this rifle
That makes sense, and of course you can build your gun your way. It was just information I hadn't entertained, and was therefore glad to have. Good luck!
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Old October 29, 2020, 12:05 AM   #10
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mcgowen notified me today my barrel is ready to ship , feels like ive been waiting forever but atleast its on the way
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Old October 29, 2020, 01:09 AM   #11
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If you want a great trigger, look at the Trigger Tech Diamond trigger.
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Old October 29, 2020, 06:19 AM   #12
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I've bought a lot of McGowen barrels including 1-off custom ones, they are pretty good at letting you know the limitations of their barrels--I would ask them what they think about your "topology." On the other hand, having dealt with them enough times, I'm going to assume they raised the gas balancing issues with you already. Looks like you're outfitting for a silencer as well. 28" hbar is a lot of mama jama weight hanging out there!

I bought a couple of those luth ar stocks and can't stand them--but to each their own as they say. I think by and large AR buttstocks have become "pimp shows" and in the process most of them can't even do the basic job of staying movement-free.
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Last edited by stagpanther; October 29, 2020 at 06:44 AM.
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Old October 29, 2020, 09:34 AM   #13
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i havent bought a stock yet , as for now im just going to swap it on my 20 inch grendels lower until i have the time to build a dedicated lower for this upper . on the other end of the spectrum i also have a 10.5 build in the works as well lol also 6.5g almost did a 300blk but then changed my mind when i saw ammo prices on 300blk
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Old October 29, 2020, 11:22 PM   #14
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I'll be interested to see how this pans out. I handled a 24" grendel at a gun show and that was what convinced me to build a Grendel. I'm really excited to see where this beast goes.

I really don't think you'll be happy with the Luth stock, unless you want to buy mine for the NIB price .

More seriously - I don't think you are building a practical gun. You are building this gun because you think it will spark joy inside you, and because you are attracted to the challenge of ELR with a Grendel. But since this gun isn't about getting max performance for minimum dollar, I wouldn't cheap out on the stock.
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Old October 30, 2020, 07:57 AM   #15
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Quote:
I wouldn't cheap out on the stock.
I pretty much agree with this, and I buy what I believe is the top performing stock for the way I shoot. This is my my current favorite. Unbelievably expensive though.
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Old October 30, 2020, 09:58 AM   #16
mel80
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yeah ill decide on something down the road we all know i can shoot witht he cheap stock i have on my 20 as it is lol (34$)

infact i like it so much i run it on all my ar's



i wouldnt mind something with an adjustable cheek rest though as with my 30 moa rail it raises my scope up .5 inch. i shuold just buy some 20/30 moa rings, but that means swaping rings everytime i wanna go night hunting, witht he rail i dont have to do that

Last edited by mel80; October 30, 2020 at 10:06 AM.
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Old November 2, 2020, 02:48 PM   #17
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got my shipping notification today so i should have it before the end of the week !!!!!

actually tracking updated ill have it lunch time on wensday

Last edited by mel80; November 2, 2020 at 06:57 PM.
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Old November 4, 2020, 02:53 PM   #18
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its here
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Old November 4, 2020, 04:17 PM   #19
stagpanther
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My McGowen barrels have always been great shooters.
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Old November 4, 2020, 07:10 PM   #20
mel80
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amazingly i can shoulder this thing and hold it steady , and its so quiet , need a std buffer and a lighter buffer spring looks like need to break everything in though to know for sure
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Old November 5, 2020, 02:39 PM   #21
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shes all setup now
except for the fact i forgot to put the bolt and charging handle in before i took the pic lol
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Old November 5, 2020, 07:06 PM   #22
mel80
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got some chrono time in today
First up is 123g eld-m over 27.7g of ar comp
Out of the 20 there's are shooting on average 2620fps
Out of the 28 I just got a string of 2792-2806fps

Next test 130 and 135's

in my 20 the 130's average 2580-2600fps im expecting a solid 2800-2850fps out of the 28 inch barrel , this thing is just slighlty slower then my 22" creedmoor and i suspect as i break the barrel in and work up my powder load specifically for this barrel that speed gap will be very minor , atm im launching 123g pills out of the cm at 2950fps
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Old November 5, 2020, 08:04 PM   #23
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Old November 5, 2020, 09:08 PM   #24
mel80
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i tested today without the suppressor , id expect a 30-40 fps boost with it based on what i see with my 20 inch barreled 6.5. i prolly wont get to do more testing and barrel breakin till next week , were going to get hit with 20-30mph wind tommorow gusting to over 45 and then a snow storm the day after
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Old November 6, 2020, 11:44 PM   #25
mel80
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i may end up with a low mass bcg after all .
suppressed the rifle cycles perfectly
unsuppressed it short strokes , first thing im going to try is a std carbine buffer and spring ,

im running this 28" upper on my 20's lower which runs a h2 buffer and heavy spring which runs flawlessly on with the rifle lenght gas system on the 20" barrel both suppressed and unsuppressed

on monday ill have a std carbine setup in my hands
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