Preparing for a first Grendel build

[wvmagnum]

Howdy, y'all. I recently picked up a stripped lower to start a new build with. After doing some research, it appears all roads lead to Grendel. I intend to build a hunter that is capable of some long range shooting, too. I'm not happy with the performance of a .223 where bear are involved, and I generally like sending larger lead downrange. Also, I already handload, so I expect to really be able to squeeze some accuracy out of this build.

With all of that said, I have some questions.
1. Stainless or not?
2. 16 or 20 inch?
3. Does anyone have experience with the AA stainless fluted 16 inch?
4. Muzzle brake?
5. Anything specific to watch out for in quality or during assembly?

I'm trying to keep costs down, but I know that's relative in building any AR. Let me know what you think, folks.

[LRRPF52]

Welcome aboard.

Many of us have a lot of experience with the AA 16" fluted barrels, which are the ones to beat right now looking at price and performance. I've built several uppers with them for friends, and they are shooters, averaging MOA across all the ones I've seen so far. Best one put 10rds into .8", worst are 5rds into 1.2".

I like 18" for a dual hunter/target light rifle, but I haven't seen any real mv different between 16" and many 18" barrels that I've chrono'd. Bill A. said he saw the same thing across larger samples in initial testing of 6.5 Grendel too, so they are usually within 20fps of each other.

I don't like brakes on the short guns. They are better suited for the longer barrel target guns for me, as I don't want a brake when hunting without ear pro.

[jim_bob]

Wvmagnum, I assume you are in The mountain state of West Virginia, if so, I'd suggest a stainless 16" tube. (I bet you'd like an 11.5" blaster even better!) The AA 16" fluted barrel is tried and proven. I shy away from brakes. There are some techniques that can be used during the build process that some reputable builders believe to improve accuracy. (I am a follower of these techniques.). LLRPF52 and Bill Alexander are a few of the gentlemen that have shared these techniques on this forum.

20" of barrel is a lot to tote up and down mountains for any considerable distance.

If you have some patience the Open Faxon 16" group buy will hopefully turn into a stainless barrel!

[wvmagnum]

Thanks for the replies. I am in The mountain state. I've heard some older guys say if you ever get tired of walking across it, you can lean up against it. They're right.

I usually whitetail hunt with a .35 Remington lever gun, or my Model 70 in 300 WinMag. Neither of those are particularly light, but even at a 20" barrel, an AR should still be shorter than the 70. Would the decrease in velocity at 800-1000yds from a 16" represent much of a decrease in accuracy at that range? I'm not worried about hunting with it at that range, but do have the opportunity to shoot that far for fun.

Why do you shy from brakes on shorter guns? Do you feel the same about compensators? I am thinking that the either would make for quicker follow up shots...you know, in case someone else misses with it.

[wvmagnum]

Also, would I truly benefit from a stainless barrel and is a carbine buffer acceptable on the Grendel or does it need the rifle buffer tube?

[VASCAR2]

I use a carbine buffer and spring with a six position collapsible stock with 20" barrel. Buffer tube length determines the spring and buffer. Rifle length buffer tube, rifle spring and rifle buffer. Carbine buffer tube, carbine buffer and carbine spring.

I personally don't like the noise with compensators with mild recoil on the 6.5 Grendel. My 20" 6.5 Grendel has plain muzzle with target crown. A thread protector or A-2 flash hider are GTG in my opinion. Basically personal choice.

[dfwpi]

Tagged

[Stumpnav]

Also getting ready to do my first Grendel build. I've looked around, but have not seen a thread or other reference on what is the best overall barrel length.

Looking at the load data, it seems you need at least an 18" barrel is needed to get good performance? Am I off target on this?

[wvmagnum]

Well, as it turns out I found a pretty good deal on an Odin combo that I will probably be ordering. I am torn between the 18 and 20 and keymod vs mlok. Need to get it ordered in, talked to the cerakoting guy today and he is a couple weeks out right now. I have also toyed with the idea of cerakoting of myself. Anyone have any luck there?

[jim_bob]

I'm pretty sure LRRPF52 does his own Cerakote. If the question was 18" vs 20", I'd go 20" for the velocity. I'd use the mounting system, keymod / mlock, that I had the most of.

[bob4432]

There are some techniques that can be used during the build process that some reputable builders believe to improve accuracy. (I am a follower of these techniques.). LLRPF52 and Bill Alexander are a few of the gentlemen that have shared these techniques on this forum.

Any way you could point a noob accuracy builder in the direction of these techniques, I tried searching but am not sure of the exact member name to search for and also the language.

Thanks in advance,
Bob

[A5BLASTER]

Here are a few tricks I learned here on this site and yes they do work.

My first grendel i bought from a member here and it would not shoot a group for nothing, I had never built a AR before but I tore it down and rebuilt it with these tricks.

First square the reciver.
Second bed gas tube into the gas block with blue locktite.
Third bed gas block too barrel with red locktite.
Forth bed barrel to reciver with blue locktite.
Fifth use lot of torque when tighting down barrel nut, might sound crazy but my rifle grouped better with 65 pounds on the barrel nut then it did at 40 pounds.
Sixth buy the best grade barrel you can afford
Seventh take the time to tune the gas system to perfect function
Eighth buy the best trigger you can afford
Ninth buy the best scope and mount you can afford and take the time to mount them both square and level and tighten down the screws with enough in pounds of torque they won't come lose,lil blue locktite helps with this as well, lap scope rings if need be.
Tenth use match grade ammo or handload.

I hope this list helps sir, I'm no expert but I did these things and I know they worked to make my rifle more accurate.

I'm sure others will post things they did to build accurate rifles.

Good luck.

[Drillboss]

Any way you could point a noob accuracy builder in the direction of these techniques, I tried searching but am not sure of the exact member name to search for and also the language.

Thanks in advance,
Bob

Here's a link to the article referred to.

http://bulletin.accurateshooter.com/2015/05/what-makes-an-ar-accurate-whitley-offers-answers/

[bob4432]

Thanks for the link , good read with some additional links. I have a BCM upper that is so tight to the barrel extension that when heated up w/ a hair dryer, I was only able to get the extension in about 2/3 of the way, I need to go pick up a heat gun for more heat. BCM says on their site that their uppers are undersized on purpose for greater accuracy, so in a situation like this where the upper is known to be undersized on purpose should I still use blue loctite on the barrel extension?

And for just any barrel extension bedding in general (AR), do I just apply it with a very short (1/4-3/8") paint brush or is there a better way?

Looks like I have a dimple jig and set screw gas block to sell .

Thanks in advance,
Bob

[bob4432]

Here are a few tricks I learned here on this site and yes they do work.

My first grendel i bought from a member here and it would not shoot a group for nothing, I had never built a AR before but I tore it down and rebuilt it with these tricks.

First square the reciver.
Second bed gas tube into the gas block with blue locktite.
Third bed gas block too barrel with red locktite.
Forth bed barrel to reciver with blue locktite.
Fifth use lot of torque when tighting down barrel nut, might sound crazy but my rifle grouped better with 65 pounds on the barrel nut then it did at 40 pounds.
Sixth buy the best grade barrel you can afford
Seventh take the time to tune the gas system to perfect function
Eighth buy the best trigger you can afford
Ninth buy the best scope and mount you can afford and take the time to mount them both square and level and tighten down the screws with enough in pounds of torque they won't come lose,lil blue locktite helps with this as well, lap scope rings if need be.
Tenth use match grade ammo or handload.

I hope this list helps sir, I'm no expert but I did these things and I know they worked to make my rifle more accurate.

I'm sure others will post things they did to build accurate rifles.

Good luck.