favorite load with 77g Sierra in 8T AR's

I have never tried the tipped versions.

I have experimented with IMR XBR 8208, Reloader 15, H4895 and AR-Comp out of a government profile 20 inch barrel. All those and many more work fine.

Seems 23.2 +/- or so on the XBR 2,675fps
24.0-24.5 +/- or so on the RL15 2,595 fps
22.5 or so with the AR-Comp 2,630 fps
23 or so on the H4895 2,675 fps

H4895 shoots the best through-out a large range. No picky areas. You can also go higher and keep the same accuracy. I have noticed using a CC#41 can net +100fps with H4895. (same accuracy/more pressure LOL)

I shoot both Sierra 77's and Hornady 75's.

Both shoot well. The Sierras seem to shoot a little better in a lesser quality barrel. In a good barrel they will be neck to neck. IMO

It is cheaper to buy a good barrel and shoot cheaper bullets after several thousands of rounds IMO.

I have a dummy round from the longest Sierra SMK 77gr i have ever measured. I seat them all so a duplicate of that will fit in the mag. Normally COAL is from 2.240 all the way back up to 2.257+

I have a bunch of ball powder loads ready for load development. When i get the time "someday" i will post back the results. I was hoping for 2800fps.

We will see...
 
Have used 24gr of TAC, Varget, 4320, RL15 . 23.2 8208 and 23.5 of either 4895. All in High Power competition with excellent results. A good barrel is the most important part.
 
I have been so dang busy with all of these farm projects i have not been able to shoot much as of late. I did however go out to the shooting range one evening weeks back with my 1st round of testing with PP 2000MR and Hornady 75's.

I used the load data (working up on my own) from a youtube video from Johny's Reloading bench. The data is way higher than anything listed. Just like him, i found zero pressure signs. Unfortunately at night my chronograph does not work. After that night i ordered a Lab Radar for future testing. Unfortunately i have not been able to go back and "re test"

The long and the short of it though, was that i like it a LOT! Through out a very respectable range, and way up top on the powder charges i found almost identical accuracy and point of impacts.

I am pretty confident i will find a nice area in the middle of that range and have a nice cushion for charge weight/volume errors and temp swings. But... re-testing will confirm and i will have my new lab radar with me.

Results to follow.

Someday..... I am too dang busy to go shooting any time soon.
 
Yes that Johnny’s Reloading Bench and PowerPro Varmint was impressive in the speed department with Sierra 77gr bullet.
When reloading supplies return this is what I want to try my self.
 
I have never attained the speeds Johny has. Even with longer barrels.

Looking forward to trying the Lab Radar out.

Generally speaking i run 100fps slower with 2 inches more barrel.

That WOA barrel he had was a keeper.
 
I've tried varget, benchmark, and AR-comp with 77tmks out of my 7 twist 20" YHM barrel. the best groupings (approximately 1/2" groups) come from Benchmark, but its very low in the powder charge range... ungodly slow.... I've tried and tried and tried to figure out a load higher in the powder range, but just haven't been able to get one to group worth a darn... I recently tested some loads with AR-Comp and must say, I like it. Best groupings (roughly 3/4") so far come .1 grains under the point where I start to see pressure signs. I haven't chrono'd them yet, but this I believe will be my new go to powder for my .223 AR
 
LittleAndy,

What charge weight are you getting pressure signs at? I went all the way until extreme compression and did not see much damage to the brass at all.

I even did multiple reloads on the brass and did not find loose pockets.

I only shoot from NATO chambers though. My guess is you have a Wylde, and likely higher velocities.

The one thing that stood out with AR-Comp is how much less strain on the gas system it made compared to other powders, especially suppressed!

On my suppressed carbine with a carbine length gas system, i opted to not use any other trickery methods except for a stiff Tubbs spring.

Over gassed, Yes! But not extremely like others where it feels like the buffer is going to come through the tube and into your shoulder.
 
What has anyone experience been on Coyotes with Sierra’s 77Gr BTHP ?
Or is it just not flat enough shooting at calling distances to mess with ?

Thanks
 
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Originally Posted By: Kino MI've killed a ton of coyotes with 77SMKs, kills great but not the most fur friendly!

I've nailed some big hogs with the 77gr SMK's.

My favorite powder right now is AA2520.

With loading supplies for 6.5 and 6.8 being difficult to get sometimes, I'll probably switch over to 5.56mm as I have several thousand rounds of 77gr SMK's to burn.
 
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