129gr Interlock, 6.5 Creedmoor load

[houser52]

Loaded up some 129 Hornady Interlocks yesterday for my Ruger American Predator 6.5 Creedmoor. While I'm very happy with the 3 shot group, I'd like to have a little more velocity out of it. I'm loading fired Starline SRP brass, just under Hornady max at 42.3gr. H4350, cci450 primers and .020" off. Averaged velocity is 2673 fps. from the 22" barrel which is in line with Hornady's online data.

Can anybody recommend another powder that'll get me more velocity and be just as accurate?

 

[Sockeye66]

Reloder 16 should be able to add more velocity than that, looking through my notes, RL16 pushed the 129gr IL an average velocity of 2790fps through a Tikka T3x SL. Other powders that would give more velocity would be RL26, RL17, StaBall 6.5, Superformance and Hybrid 100v.

 

[houser52]

Thanks. I have RL16, Staball and Superformance in the cabinet. In your opinion, any one of those more accurate than the other?

edit- I just tried a near max load of Varget and Hunter. Both had less velocity than H4350.

 

[Creedmoor shooter]

Have you actually ran it up to pressure with h4350? My 140 eld-m load is faster than that with my 22in using h4350

 

[houser52]

I have not seen any signs of high pressure at that charge weight however the primers were starting to crater a little but still have rounded edges. I know that cratering is not a 100% indication of high pressure.

 

[Sockeye66]

Thanks. I have RL16, Staball and Superformance in the cabinet. In your opinion, any one of those more accurate than the other?

edit- I just tried a near max load of Varget and Hunter. Both had less velocity than H4350.

RL16 in my experience is as good as it gets for the 6.5 CM for accuracy and velocity, it's temp stable and fills the case optimally. I'd try the 16 followed by Staball and then the Superformance. Might try a ladder from the low 41's and go .3's from there and find the pressure. I haven't used the Starline brass so that might be a consideration for charge weights in regards to case volume. Your CBTO length is out from the book length (.050 neighborhood) which may allow a higher charge weight for more velocity. Most importantly, be safe, work up low and slow, and pay close attention. BTW, if the brass is virgin, this can also have an effect on pressure/velocity.

 

[houser52]

Thanks.
I usually start all my loads .020" off from touching the lands and adjust OAL from there. The Starline brass has been fired 3-4 times, trimmed as needed, shoulders bumped .002-.003" with a Redding body die, neck sized with a Lee Collet die and annealed at least once. I'll try increasing the H4350 charge by .3 at a time until I see obvious pressure signs then back it down.
If that doesn't work out I'll try RL16.

 

[Pdyson]

Weird…my Sig cross has a shorter barrel and I'm loading a full grain less of H4350 and matching your velocity with the ELDX. Only other difference is I'm using Fed small Match primers in Lapua brass.

if you want want a fast load take a look at reloader 26. I didn't finish load development on them but I loaded some Berger 135gr Classic Hunters in my Sig Cross 18" barrel Creed. I used 48.9 to 49.8gr of RL26 In .3 gr increments. Velocity avg was nothing short of astonishing! My starting velocity was 2887 SD 8 on the low end up to 2950 SD8.6 @ 49.8gr. Groups were not that great, just 1moa up to 49.5 and the group blew up to 3 MOA at 49.8. better yet there were zero pressure signs. I ran out of Berger's before I could do some seating depth tuning. Im going to circle back and make this load work for hunting season next fall.

 

[VinceMule]

Cratered primers does not necessarily mean high pressure, over size firing pin hole in the bolt is usually the cause.

R#17 with a large primer brass.

 

[Dmagna]

Why not load up a higher charge? Is your rifle showing pressure signs?

 

[houser52]

Why not load up a higher charge? Is your rifle showing pressure signs?

See my posts #5 and #7

 

[Dmagna]

See my posts #5 and #7

Oh. Keep going on the h4350, it will give you what you want.

 

[houser52]

I took y'all's advise and increased the charge . Beginning at 42.6 gr. and increasing by .3 gr up to 43.8 gr. Pressure was still ok at 43.8 gr but I backed it down to 43.6 grs and shot a 5 shot group. It looked pretty good so I stopped there.
Thanks for the help.

73°, 11 mph SW wind, 2760 fps average.

 

[Sockeye66]

That's a solid group for having a little wind and good speed too. Glad it's coming around for you. Once it's dialed in and if you have the extra components, give 16 a try and see which works best.