Gun powder help 77gr Sierra MatchKing.

Tech4

Active Member
Joined
Jan 1, 2020
Messages
33
Location
Greene NY
I am using 55gr and want to develop a load for 77gr Sierra MatchKing for my 5.56x45. I will be using it for long range and have a 16" barrel. I was wondering what powder or powders I should try.
 

brentc

Well-Known Member
Joined
Apr 3, 2009
Messages
2,397
8208 XBR and Varget are a couple of solid temp stable choices. RL15 if you can deal with a little temp sensitivity.
 

sable tireur

Well-Known Member
Joined
Oct 8, 2010
Messages
1,480
Well, the stupid upgrade destroyed my post and the information I was supplying. What a joke to upgrade first thing in the morning while people are checking the forums.

Will this load be magazine fed or single shot? I'm guessing magazine since you're using that short barrel.

Twist rate? Have you checked to be sure the twist is enough to handle this bullet?

Define long range since a magazine length combination will run out of steam (subsonic) before 1,000 yards.

You can entertain using:

VVN-530
IMR-3031 (don't laugh, this is a superb powder for this combination)
AR-Comp
8208
 

Wingnut00

Active Member
Joined
May 20, 2019
Messages
28
Location
Wyoming
H-322. Start at 21 grains and work up. 2.250 oal with a 450 magnum primer. 22.3gr is my load with 77’s.
 

johnnyk

Well-Known Member
Joined
Dec 24, 2001
Messages
2,139
Location
Potters Hill, NC
Straight from Hodgdon Reloading Data Center; heavy bullet load: CFE 223, Varget, IMR 4895, IMR 8208 XBR and BL-C(2).
 

Dirtrax

Well-Known Member
Joined
Mar 23, 2014
Messages
153
8208 xbr for 5.56 wylde. 2800 fps w/77’s out of an 18” barrel. 1/7 twist and 1/2 moa to 600yds loaded mag length.
 

TRG65

Well-Known Member
Joined
Dec 21, 2017
Messages
167
As noted before, 23 grs is a good place to start. I'm running 23 grs of Varget with the 77 at mag length for an AR. I'm getting an average of 2540 from an 18" barrel. The velocity isn't anything to write home about and I'm using range brass, so I'm getting a miserable SD, but it will shoot a consistent sub-MOA for me and this was the only load I could get below 1.5 MOA
 

RT2506

Well-Known Member
Joined
Jan 10, 2008
Messages
1,927
The biggest problem you will have is to FIND SOME IMR 8208 or Varget. LOL Seems to be sold out EVERYPLACE.
 

DavidleeCole

Well-Known Member
Joined
Nov 7, 2014
Messages
141
Location
Bonneville Arkansas
I love CFE 223 with my 77 SMK 23.5gr. It shoot well at wag length and makes first round hits out to 440 yards on 10 plate every day no matter. I just have a 1×4 power scope so I have not went out past a quarter with it. Ont the terminal ballistics end I have killed 11 deer with this load taken two or more every year for the past 5. And the kids love it too. I shoot an AR with an 16" 1:7 twist and get 2540 fps.
 

Latest Classifieds

Nightforce has great tracking capabilities, they are rugged, a bunch of elevation, holds zero forever, and reticles are designed for long range shooting. So if you are looking to shoot long distances constantly, then you need a scope that can take the abuse. -- gilmillan1


Culture Of Excellence At Nightforce Optics
By Len Backus

A high level of quality both in production and in service. Read More


Nightforce is such a solid combo of reticle, available elevation, glass that is good enough to shoot at the longest range you can dial. Nightforce has bullet proof construction that can handle the incidental horse rolling or some other rodeo action. -- bigngreen


Nightforce ATACR Scope Review
By Jeff Brozovich

The new NightForce ATACR is for sure a top choice for any long range shooter. Read More


The total package. Nightforce is the best I have used as far as turret feel and solid detents. I have never had one that didn't track right on and always return to zero. Nightforce NXS is the best value for everything I need. -- Broz


Nightforce Velocity 1000 Reticle Review
By Scott Shreve

I think Nightforce knocked it outta the park with this reticle! Read More

NightForce


Top