Handguard length on 18" barrel

[Techfixer87]

Building my first Grendel from an 18" barrel I traded for recently.

I plan I hunting with it so trying to keep it on the lighter side but of course want it balanced.

What lengths has anyone else used on 18" AR builds? Pics would be cool to help with ideas.

Also still digging up info on the basics of the round. I know I will need specific mags, are their mags anyone would recommend?
I seen there are two types of grendel chambers. Is one superior to the other if so how?

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[solv3nt]

The grendal and 6.8 SPC are supposedly picky about magazines. I bought precision reflex for my 6.8 but I'm yet to shoot it. They are some spendy magazines though.

Grip length is somewhat determined by the gas system in that it would look silly to have a carbine grip with a rifle gas system.

18" Wilson Combat, fixed stock, Geissele trigger.

 

[titsonritz]

I have a 15" handguard on my 18" SPR.

 

[P7M13]

I run several rifle length systems. Used to put 15" Hand guards on them, but needed to put together a build for a quick test and all I had in my parts bin was a 13.5" handguard.
On Rifle length gas, that leaves the gas block half covered.
I like the look.
I also found, I liked how the rifle handled. It's purely psychological, but the four to five inches that hang out past my hand when I hold the rifle off-hand are bothersome.
I don't play GI Joe or engage in war games, so I'm not concerned about protecting the gas block. Besides, I've pinned it. so I am not concerned about it moving.

 

[Techfixer87]

I believe mine is mid length, should I be considering am adjustable gas block at all or even a buffer on the heavier end? I appreciate all the answers guys.

I was thinking of going fixed stock on it as well. As this will be my longest barrel I figured a more full looking backend would make it look more equal I guess you could say to the extra barrel length than I'm use to having or seeing.

 

[solv3nt]

I believe mine is mid length, should I be considering am adjustable gas block at all or even a buffer on the heavier end? I appreciate all the answers guys.

I was thinking of going fixed stock on it as well. As this will be my longest barrel I figured a more full looking backend would make it look more equal I guess you could say to the extra barrel length than I'm use to having or seeing.

The adjustable will give you the most options for ammo. I'm kind of cheap, I just grab a little heavier buffer. I was running an H2 on a carbine 5.56.

 

[P7M13]

The adjustable will give you the most options for ammo. I'm kind of cheap, I just grab a little heavier buffer. I was running an H2 on a carbine 5.56.

Cheap to a fault, here.
The longer your barrel, the less recoil force you will experience. Hence, probably won't need an adjustable gas block.
I had an adjustable GB on one AR10. Tuned properly for one specific round, it wouldn't cycle properly for other rounds. Wound up opening it wide open and leaving it there. Ended up adjusting the weights in the buffer to optimize the performance. No buffer weight bottoming out on the springs, and will cycle every ammo I run. You can do the same for the AR15, but I find COTS to be sufficient. I'm not trying to build race guns.
The most important parts: Barrel, trigger, optics
Next : BCG and magazines -- if either of these suck, you're as good as dead-in-the-water.
Last (aesthetics) : hand grip, fore end and stock -- though these have the greatest effect on how it feels when you use it.

@solv3nt wasn't cheap when he went with PRI magazines. I've tested PRI, C-Products, ASC, Magpul and one other (cannot remember) PRI are simply the best, most reliable and best feeding. I have a stack of all those brands for both 6.5 Grendel and 6.8 SPC. What I found is I can use them interchangeably.

 

[monkeybutler]

I don't mean this in a snarky way, but for pictures try google images. E.g "18 barrel 12 rail" will get you a bunch of relevant pics.

I have a 12'er on my 18" grendel. I don't expect a longer rail would do much for me. The gas block is pinned so it being exposed is a non issue. For a non critical hunting rifle it would not matter much if it was not pinned though.

I think just about everypne is using the type 2 chamber at this point, which is oddly named since it is the original chamber developed by Bill Alexander and that Finnish dude. Regardeless, that is the one you want.

PRI mags as others have said are about the best you will do. Another rule of thumb is that smaller magazines work better, e.g. I would expect a five or ten rounder from a marginal brand to work better than their 26 rounder.

 

[Techfixer87]

The adjustable will give you the most options for ammo. I'm kind of cheap, I just grab a little heavier buffer. I was running an H2 on a carbine 5.56.

I'd pretty much be finding a good handload to stick to since it's mainly for hunting. Maybe my start at longer distance shooting as well but we'll see.

 

[solv3nt]

I'd pretty much be finding a good handload to stick to since it's mainly for hunting. Maybe my start at longer distance shooting as well but we'll see.

I built my 6.8spc more for hunting than SHTF, I've already got a 5.56 with an ACOG for that.

 

[No_Regerts]

One on the bottom is 18 w/15 inch Geissele handguard.

 

[Xaevian]

I have a few AR Stoner 25 rounders I had no issues with.

 

[msgriff]

Mid-length gas, from receiver rail face to the gas journal shoulder, is ~9.32".
Rifle length gas, from receiver rail face to the gas journal shoulder, is ~12.71".
Add 1" for a standard low profile gas block plus ~0.025" for the cap gap.
AGB's with front adjustment screws will be longer.
This will give you an idea of minimum handguard length to cover the gas block. Keep in mind that "brand X" 12" handguard might not be exactly12".
I usually run 12" for mid gas and 15" for rifle gas, but for a 18" barrel mid gas, I would go with a 15" handguard.
Here's a 18" .308 RLGS with a 15" Aero S-One rail:

 

[bentoncity]

16" barrel & a 12.5" guard. Covers the adj. gas block on both.
308 & 5.56

 

[titsonritz]

plus ~0.025" for the cap gap.

My notes say 0.028"

 

[titsonritz]

16" barrel & a 12.5" guard. Covers the adj. gas block on both.
308 & 5.56

A 10" handguard is the will cover a LPGB with a mid-length gas system.

 

[titsonritz]

Here is a BCM 10" rail with a mid-length gas system...
https://bravocompanyusa.com/bcm-sta...ted-upper-receiver-group-w-mcmr-10-handguard/

 

[bentoncity]

5.56/16" bbl. Luth AR Buttstock
Aero Precision Forend

 

[v0lcom13sn0w]

Building my first Grendel from an 18" barrel I traded for recently.

I plan I hunting with it so trying to keep it on the lighter side but of course want it balanced.

What lengths has anyone else used on 18" AR builds? Pics would be cool to help with ideas.

Also still digging up info on the basics of the round. I know I will need specific mags, are their mags anyone would recommend?
I seen there are two types of grendel chambers. Is one superior to the other if so how?

15" handguard 18" barrel on my grendel

 

[v0lcom13sn0w]

Building my first Grendel from an 18" barrel I traded for recently.

I plan I hunting with it so trying to keep it on the lighter side but of course want it balanced.

What lengths has anyone else used on 18" AR builds? Pics would be cool to help with ideas.

Also still digging up info on the basics of the round. I know I will need specific mags, are their mags anyone would recommend?
I seen there are two types of grendel chambers. Is one superior to the other if so how?

#1 e-lander mags. #2 C products mags

i have 25 round mags but never have used them. i use the 5 rounders the most due to big game hunting regulations in oregon