Home Forums Hunting & Shooting AR and Tactical Rifles 77gr AR15 Load Preference?

JPro,

If you're not using ASC stainless steel mags in your AR's , you might want to try one or two. They allow a COAL of 2.315" instead of the standard 2.260".

LINK

Ed

Good inputs today. I appreciate it.

Ladies,

Understand that Beezer's Ninjaness is a fhuqking ruse and her CLUELESSNESS is simply fhuqking Magnificent. Hint.



Bless her heart for trying.

Fhuqking LAUGHING!.............

Yep, you have to push 8208 pretty hard to get 2700+ FPS, IME; ditto for AR Comp but both are good powders.

You don't have to push as hard to get there with both VV-540 or 2000MR though..............never used Lever, some say it's very good too.

MM

I gonna say that I think you're way over any pressure that I'd want to be at with that load if that's a real velocity................I can't quite get there with that load form an 18" barrel.

MM

Varget is hard to beat for pure accuracy, as long as you don't need / want top velocity attainable with other powders.

MM

I'm not getting any pressure signs at all. Unless both my chronos are bunk, but the drops line up with Ballistic FE. This load has been fired in several different rifles as I outlined before.

The listed load should be on the top end but not overpressured. It’s your velocity from your 16” barrel that is higher than what everyone else is getting even from an 18” barrel. Something isn’t jiving

I don’t get 2700 fps in any 16” barrel I’ve had which includes Colt, Daniel Defense, LaRue, Noveske, Krieger, Sionics and a few others I’m forgetting.

Doesn’t matter really as long as others reading this understand they won’t get your velocities. MK262 in the original 18” Douglas SPR barrel doesn’t get your velocities and it uses a blended powder we can’t get.

Not the 77 grain, but I tested Lever with the 75 gr. Bthps and at 26 grains was seeing 2831 fps and that did show pressure. 25 grains was showing 2699 fps with no pressure signs and this is in a 16” CLE Douglas barrel.

My 77 gr SMK load is 23.4 grains 8208 which is around 2670 fps out of that 16” barrel.

You know, next opportunity, I'll chrono out of some of my other 16" barrels to see what it does. One difference can be the actual barrel is a fast one. When one has been doing this a while, you may discover that two identical guns will get significantly different velocities with the same ammunition. I have had both fast and slow barrels. Additionally, adding a suppressor often adds velocity to a rifle, a point many here are overlooking. Pulling off the can, according to my notes, shed 30 fps on average.

I’ve been chasing the MK262 load since it came on my radar. And yes I too have had some fast barrels, a 17” Krieger from CLE was almost as fast as my 18” Noveske, much faster than my 16” Noveske. You may have a one in a million barrel but the rest of us are not getting that velocity with 18”.

I will find out next few days I loaded up his exact same load even had cci 41. Will report back, I will shoot them out of 2-16 inch (bear creek barrels) 3-18 inch (2 BA 1 green mtn) 1-20 (bison armory) over magnetospeed.

Barrels are weird. You never know what they are going to do. I tested some loads over a chrono once with 2 of the same manufactures barrel, a Noveske and a 22" Savage bolt action.

All the AR's were using 20" tubes and they were all faster than the 22" bolt action Savage. What surprised me the most was the difference in velocity between the 3 AR barrels.


I would have thought the 2 from the same manufacture would have been roughly the same, but they were not. There was about a 60 fps difference from the slowest to fastest. If I remember right, my favorite rifle was the slowest, but also the most precise. Weird anomaly that I can not explain.


Avg velocity of that load was 2,680 fps. That's as fast as I wanted to push the AR Comp load..

What is funny is a friend of mine bought an 18" BCM SS410 when I bought my first 16". With the suppressor my 16" was 3 FPS slower average than his 18" with the same load on the same day. Without the suppressor it was around 20 fps. I don't remember the velocity on that upper, its not in the notes on my phone, but I want to say it was 2720s. That first SS410 is long gone and wore out, and I'm now on my second one, but this time the KD4 version.

You're right, the barrel isn't making the difference, most likely different people assessing pressure differently.

I can remember with Barsness commented about the development of the 7mm STW............when they finally got around to actually measuring pressure on the developer's "magic" loads, they were WAAAAAAY over any acceptable pressure level.

I strongly suspect that's the case here as I have never, in print, or reality, with over a dozen guns personally, seen anyone referencing getting that kind of velocities from that combination in a 16" barrel. Ever.

MM

Do you guys think it may have been a faulty chrono?

Hard to say.............it could. Lot's of people just never see pressure signs though.................just sayin'.

All I know is that on all the forums I've been on, & all my direct experience, no one has ever referenced 24 gr of 8208 getting 2770 from a 16" barrel................& I don't either from 16" or 18" barrels; don't have anything longer.

Doesn't mean it can't be done, but it does mean it's surely not an everyday occurrence.

(And 23.5-24 gr of 8208 is my top load with 77's with that powder as well. I've mostly gone to VV-540 & 2000-MR instead of 8208 as I can get more velocity than with 8208 or AR Comp with the same accuracy, but 8208 is a very, very good powder for me & I like it a lot)

MM

No. It’s not a faulty chrono. When the drop data lines up out to 1200, it’s right.

Yeah, barrels can make a difference. So can chambers. Sometimes two identical barrels may have 40 fps between them. It’s just the way it is.

When it comes to pressure signs, they are either there, or they aren’t. Hell, about half of ARs will shoe ejector marks with 5.56 NATO ammo. Others, not so much. Usually, 5.56 ammo loaded to the pressure will see primer pockets blown in 4 or 5 firings. Meanwhile, the real tell is a chewed up extractor groove and rim.

On 2000MR I have a couple pounds. I used it and it was about the same speed as 8208, but wasn’t as tight for me. In the grand scheme of things, too much emphasis is placed on speed. 50 fps really doesn’t matter much in the grand scheme of things. Pick out the best shooting one. If it’s faster, it’s just a bonus.

So if it’s a magic barrel then it should be magic with any ammo. Chrono some M193 and tell us what it runs.

Makes me want to sprinkle some magic fairy dust into some 223 cases and run to the range with the chrono.. ha ha..