This build to way to long but it's finished, 6mm arc

270OKIE said:
Hmm, my Areo upper and Ballistic Advantage barrel were a very tight fit with no slop at all so it must be luck of the draw.
Click to expand...

The BA barrel was a slightly snug fit, as is the McGowen I replaced it with. But it is well established that if you want the most accuracy, the upper needs to be honed square and to bed or shim the barrel. I had a hard time finding a small amount of .0005 shim to wrap the barrel extension for a heat and shrink fit, so I used the high heat sleeve retainer instead.
 
270OKIE said:
@troy fairweather here's my 223 DMR for comparison and maybe a bit if enabling.
As you can see, we have similar taste! I got my 20rd usgi mags and A2 stock kit from Fulton Armory. I need to swap the KAC buis over to my 308...
View attachment 1141410
Click to expand...
Ya you had posted it recently I believe, my gun has been together since November 22 apart from a few things. I was hoping to have it ready for deer season but didn't get it ready in time. On grips I'm back and forth with the l
Larue( nice for the money) and a DD I have. The larue is comfy but with it was a touch longer and I don't have big hands really. I may get another of these stocks there nice for $20, as good as $50 ones. Think sarco had some originals with the aluminum butt, I'd like one of those.
 
troy fairweather said:
I wanted the lite stock but really wanted to try the a5 tube and buffer but one of the other was always out of stock, then when I got the leupold mount line of sight is about perfect and don't think I'd need the check piece on the magpul. Plus that presma stock was only $20 and I have the rifle buffer parts.

How you like that aero block, I was going to try one but was always out of stock for the sale price, got my sa block on sale for $70 so good deal. I wanted to use the jp block but the gas block journal on the Shaw is 1" long and the jp block I wanted is 1 1 /8 of 1/4 long so some would be in the air where the barrel steps down to .740.
Click to expand...

Aero block is comparable to any of the other "click adjustable" and maybe even better at releasing the excess gas from the looks of the soot coming out of it. I even put them on my two other 556's because I like them. Price is good if you look around.
 
The thing that really surprised me was just how far out of square the upper was.

I pulled my couple 556's apart that I put together 6ish years ago with Aero upper/lowers, and all the lapping tool did was remove the anodize in a perfect circle because they were already square. Also, they were a much closer fit inside diameter.
 
M-14 said:
Aero block is comparable to any of the other "click adjustable" and maybe even better at releasing the excess gas from the looks of the soot coming out of it. I even put them on my two other 556's because I like them. Price is good if you look around.
Click to expand...
ya there a good price, where I ordered most of my stuff they didn't have any otherwise I would of got one, they seem to be a bit of a sa copy. My block blacked my barrel in the rounds I shot.
 
troy fairweather said:
Ya you had posted it recently I believe, my gun has been together since November 22 apart from a few things. I was hoping to have it ready for deer season but didn't get it ready in time. On grips I'm back and forth with the l
Larue( nice for the money) and a DD I have. The larue is comfy but with it was a touch longer and I don't have big hands really. I may get another of these stocks there nice for $20, as good as $50 ones. Think sarco had some originals with the aluminum butt, I'd like one of those.
Click to expand...
I second the LaRue APEG grips. I like the UDE color myself. It's like a tan grey combo.
 
I really like the feel of these dimondhead handguards not sure if they still make this one anymore, I know they had a round and this one is the triangle type and there very comfortable. Only thing is there's only holes to attach anything on them and I'm not sure if other rails will fit the hole spacing of the contour.
Other thing I had to trim the set screws flush for the gas block, they were about touching. No there's maybe a bit more then 1/16" maybe more and I'd feel better with more space . There plenty of meat on the bottom of the block to take off a 1/16" or more so it may meet the grinder one day to put my mind at ease , but I hate doing stuff like that. There quite heavy handguard to, not that it matters on this type of gun but get its 12-15 oz.
 
I like it, it's very similar to the Valkyrie I built my first barrel was a 22". I do wish the ARC would have come out first though IMHO the Valk just doesn't quite work as advertised, it doesn't have the powder capacity to run the 88 and 90s fast enough at mag length from a 20 or 22" barrel. Maybe when this barrel is toast and if the price of ammo settles down a bit.
 
troy fairweather said:
I don't think I'd need the check piece on the magpul.
Click to expand...

I started with Leupold QRW low rings because I already had them on the um, ...lackluster... 44mm scope I started with. When I went from that to a 50mm, I bought Leupold PRW high rings to clear the upper, and while the scope easily cleared the rail it was just uncomfortable (for me). From there, I added the Leupold rail riser and brought the cheek riser up to suit. Now I find it easy to locate my cheekbone "sweet spot" consistently without forcing it.
 
M-14 said:
I started with Leupold QRW low rings because I already had them on the um, ...lackluster... 44mm scope I started with. When I went from that to a 50mm, I bought Leupold PRW high rings to clear the upper, and while the scope easily cleared the rail it was just uncomfortable (for me). From there, I added the Leupold rail riser and brought the cheek riser up to suit. Now I find it easy to locate my cheekbone "sweet spot" consistently without forcing it.
Click to expand...
The leupold mount I have is 1.4" which is on the low side for ad mounts, I may have to pull of the check if I get prs lite. So sucks not using that feature but the cantted butt adjustments and flat bottom for the rear bag would be nice. I am worried about length of pull to, the a2 is about max for me and a a1 would be better. Believe the prs lite is a bit longer then the a2 stock.
 
Looks like diamondhead is out of business, wonder why they went belly up there stuff was Mosley well liked and decent quality. Looks like the magpul (L5 ?) Rail sections can be made to fit the diamondhead handguards. Not having any picattiny attachment stuff for bipods I really just need to attach a sling stud more securely to the handguard then how I have it now.
 
troy fairweather said:
Looks like diamondhead is out of business, wonder why they went belly up there stuff was Mosley well liked and decent quality.
Click to expand...

I agree, on all counts. The only thing I can assume is that the lacking modularity bit them in the butt. Their add-on pic rails were proprietary and expensive, and they weren’t terribly aesthetically pleasing when mounted, so the high price of their handguards coupled with cumbersome modularity compared to competition, I would guess their volume was slow, and their limited footprint made them vulnerable.

But I really liked their “tri-oval” handguard profile, it settles really well into support bags. And the chisel point angle of their handguards was neat, even if it did kinda complicate building with some gas blocks.
 
Varminterror said:
I agree, on all counts. The only thing I can assume is that the lacking modularity bit them in the butt. Their add-on pic rails were proprietary and expensive, and they weren’t terribly aesthetically pleasing when mounted, so the high price of their handguards coupled with cumbersome modularity compared to competition, I would guess their volume was slow, and their limited footprint made them vulnerable.

But I really liked their “tri-oval” handguard profile, it settles really well into support bags. And the chisel point angle of their handguards was neat, even if it did kinda complicate building with some gas blocks.
Click to expand...
They did start making this type handguard with mlok slots but probably to little to late for them, it's is one of the most comfortable handguards in the hand I've used and like you said works well on bags to. It's very ridged for how there attached but there pretty heavy, hope maybe some other company makes one similar but lighter and more modular. I'll keep a look out maybe there will be some diamondhead heavily discounted in the future.
 
troy fairweather said:
My buddy today gave me a box of sierra 107 hpbt, think they will work pretty good in the 6arc.
Click to expand...

Should, Sierra makes a decent enough bullet, soon as I find a decent deal I'm going to get at least 500 Hornady 105 BTHP. I've seen people with excellent results, at the range available to me the tipped variety are just a waste of money.
 
M-14 said:
Should, Sierra makes a decent enough bullet, soon as I find a decent deal I'm going to get at least 500 Hornady 105 BTHP. I've seen people with excellent results, at the range available to me the tipped variety are just a waste of money.
Click to expand...
Don't know if the 107 will be the best in the arc have to see it maybe a bit long to get the most out of it. Lgs had a few 500 boxes of the 105 wish I had the money if buy a few, seems like my barrel likes them 105s and the 108, still need to shoot more tho.
 
That long barrel in 6arc is pretty much a 25-06 just in a case that fits a standard AR mag well, as it's going to have a lot of reach-out-and touch.

And, I still contend that a 16" 6arc would be a handy thing for coyote-sized nuisance critters. And not needing long shaded scopes so much--so, perhaps an argument for a chevron RDS and a tip-out magnifier. Maybe.

@troy fairweather has an excellent build.
 
troy fairweather said:
Don't know if the 107 will be the best in the arc have to see it maybe a bit long to get the most out of it. Lgs had a few 500 boxes of the 105 wish I had the money if buy a few, seems like my barrel likes them 105s and the 108, still need to shoot more tho.
Click to expand...

I don't see why 107Gr bullets would cause any issues as far as length goes. I shoot the Hornady 108Gr that is loaded with ELD Match bullets out of my 18" Odin Works barrel all the time without any issues. I have only tried the three available factory rounds in mine and the 108Gr shoots the best for me.
 
Last edited:
OAL using long, high BC bullets is going to be limited by the magazine before the projectile reaches the lands and will only increase with wear, so that is the limiting factor with gas gun.
My ASC mags measure 2.30 inside, so subtract .010-.015 for feed reliability, that still allows +.025-.030 to explore.

Getting speed from a long bullet is compounded by decreased (effective) case volume from the bullet protruding past the neck into the case, and can dramatically effect (increase) PSI.
 
Last edited:
You must log in or register to reply here.

Similar threads

12Bravo20
  • Locked
My 6mm ARC build
Replies
2
Views
253
12Bravo20
12Bravo20
H
  • Locked
Looking for an accurate 6mm arc MSR 20’ barrel
Replies
9
Views
578
Dustbowl
Dustbowl
Z
  • Locked
6mm arc questions
Replies
4
Views
3K
z7
Z
G
  • Locked
Flat Dark Earth Build
Replies
3
Views
477
Pat Riot
Pat Riot
C
  • Locked
Finally shot my LR308
Replies
16
Views
611
citizenconn
citizenconn
Back
Top