Range Report: 69gr Sierra MK vs 68gr Hornady Match

[joeg26er]

Range Report: 69gr Sierra MK vs 68gr Hornady Match

1/9 twist CL 16" middy, 3x magnifier, 2 MOA Aimpoint

100 yards

23.8gr W748
WSRP
S&B case
2.212 COL

68gr hornady - one round very high and right - 9 other rounds - WKW (who knows where)
velocity 2500fps

69gr Sierra Match King - rounds 1" low and left
10 rounds about 2"
velocity 2500fps

control group was 55gr Win bulk FMJ BTWC
27 gr W748
velocity avg 2900 fps
group sizes approx 1 MOA

Anyone know WTH is wrong with the Hornady loads
how to improve either of these 68gr and 69gr loads?

1/9 should stabilize up to 77gr according to general research...

 

[jpwilly]

I have found that some 1-9" bbls don't stabalize anything heavier than 62gr pills. Some will shoot everything up to 77gr My DPMS wouldn't stabalize the 68gr Hornandy bullets they were made keyholes on the target because they were tumbling.

 

[kelbro]

I could never get that particular Hornady to shoot. Every other Hornady bullet that I shoot performs very well.

 

[jim147]

For your WKW.
You need a bigger target.
They may have been a 1/2" group just not on your target.
They may have been a two foot group.

jim

 

[smokey262]

If it is safe in your rifle, I would add more powder to increase the velocity which will increase the stability, and then try shooting at a closer target to see where they impact

 

[joeg26er]

more powder

I did try 27 gr of W748 with the Hornady 68gr and they grouped into

drum roll

8 to 10 inches

at 2750 fps

guess I'll be giving up on the HOrnady's...anyone want to trade me for some 62gr?

 

[ForneyRider]

My 69gr SMK and 75gr Hornady BTHP are about the same at 100 yards.

24.5gr R15 for the 75gr.

24.5-25.5gr R15 for the 69gr.

I get around 3000fps in 20in DPMS AR.

I am going to lower the powder charge to see if I get anything. the 24.5gr is much more enjoyable to shoot and I get back on target more quickly. Some folks are shooting these heavier bullets @ 2700-2900fps in the longer barrels.

I'd get a 10x power scope or better for anything less than 1MOA testing. Also a good trigger job.

I prefer Remington brass of S&B or other brand. Prep it all the same, also weight sort the brass and bullets. Haven't used W748, have been very happy with Varget and R15 for the heavier .223 bullets.

Quick and easy match prep includes: FL sizing same headstamp brass, weight sort, trim to length, chamfer, uniform primer pocket, deburr flashhole.

I'm using a RCBS ChargeMaster for weighing charges. It is more accurate and faster than trickling or using the Lee Perfect Powder.

I'm seating bullet for 2.25 OAL, I don't get consistent operation with PMAG at 2.26.

Try a V-Max bullet, they are cheap and accurate.

 

[ny32182]

First thing I would do is load them a lot longer, out to mag length of 2.26".

Also, 77gr is too heavy for almost all 1:9's as a general rule... the 69's are as heavy as I would go.

I shot some of the 68gr Hornady's in my 20" M16A4 clone (1:7 twist); they shot just as well as other match bullets I have tried in that gun.