montana Wrote:It depends on how gas efficient your rifle is. The adjustable or non adjustable gas block seal between the barrel and gas tube, the size of the barrel's gas port, the gas tube-bolt carrier key "chamber size" seal, the size of the 3 bolt carrier chambers, muzzle break or none, the bolt's support shoulder's size, the OD of the bolt's firing pin barrel, the friction between the bolt carrier and the upper's BCG channel, the recoil spring type, the friction between the trigger, magazine and bolt carrier, the weight of the BCG. Then the ammunition you are planning to use, will determine the best buffer, bolt carrier combination" if recoil mitigation or reliability is your goal. Every rifle build should be head spaced, and the throat size checked..
Yes, considered many of the above already, but still wasn't sure if I could get away with not experimenting on buffer/bcg or if there is 1 generally known answer as there often is for the less standard AR calibers. As you can probably guess from my build notes, I'm leaning more towards recoil mitigation instead of reliability, but am not trying to win any competitions or other controlled environment shoots with this either where one generally does have to sacrifice some kind of reliability or robustness outside of ideal conditions.
Klem Wrote:I would go easy on gluing the gas block, and maybe even the barrel unless it is a loose fit. If you build AR's then at some stage you will be thinking of pulling them apart. Once glued, joins are not impossible to break but it becomes a pain and might dissuade you from tinkering.
You only need to add glue to the gas block to seal it from leaking gas. The design accommodates the joins in the gas system leaking like a sieve. You only need to keep this from happening if you don't have enough gas to cycle the action reliably. I recommend building the gun and then taking to to the Range to check with the mildest loads you are likely to use. Open the AGB right up and if you still need more gas you can pull that section apart and reassemble using glue. Otherwise you don't need to seal it. That said, you are very unlikely to need it.
Making the cycling system lighter in the hope of mitigating felt recoil does not make sense to me. I would think the opposite will do this. .......
Heh, I have been there with the stuck on parts before (not by me). Completely agree. I did use a high temp but low bond strength thread locker between the gas block and barrel once and didn't feel it offered any benefit over just turning gas up/down depending on how much bleed off there was.
Regarding mass, I thought the same in the past that more mass = more inertia to stay still = less recoil in all situations. However, in experimenting (YMMV), if I had the same gun with the total mass and same ammo/load (let's assume it's appropriate and reliable per individual goals), I have found that using low reciprocating mass + easier to move parts (such as lighter buffer, springs, etc.) resulted in a different kind of felt recoil and muzzle movement than the same gun with more reciprocating mass. Based on the characteristics / differences, I am leaning towards lighter reciprocating parts for this build. Again, YMMV per so many different factors and I could easily see that for some people they would prefer extra mass in everything.
Growler Wrote:... The Odin works adjustable seems like the lowest profile I could find. Even with it, many handguards Id like to use wouldnt clear.
If you can shoot a rental or loaner before you commit to a specific trigger, Id recommend it. The roller trigger is a competition optimized design. For target and hunting, it might disappoint, or you might dig it more after the comparison. Either way, playing the field first is a win.
ETA - there are many happy LaRue MBT customers here. Myself, I cant give an opinion, since I drank the ALG/Geissele Kool-Aid.
Yep, was leaning towards an Odin block already, have had good luck with those, and luckily I also generally prefer a slightly larger hand guard around 1.7 or 1.8" OD (think roughly ALG size handguard). At the same time I didn't know if people here have found quirks with certain gas blocks not working well with this caliber or certain barrels, etc.
I've tried a lot of triggers out there, but so far my favorite for anything that may be "duty" (which I am not "duty" so maybe I actually have no clue) is the Wilson TTU Single Stage, standard weight, not the heavy one. For stuff where I want to go fast or just want something that really fits me it's the Hiperfire Reflex or Competition. Precision is Elft triggers. I have not tried the JP roller trigger or Timney AR trigger though so thought I'd ask. If the Timney feels like their bolt action triggers, then I'd actually lean more towards the Elft (Timney stuff is good IMO, but based on a conjecture/approximate triangulation it's just not 100% ideal for my preferences when shooting semi-auto).