• This Forum is for adults 18 years of age or over. By continuing to use this Forum you are confirming that you are 18 or older. No content shall be viewed by any person under 18 in California.

Sierra 150 grain 6.5 Matchking

3/8 looks like a record to me....

New Edit to this post.... I AM NOT MAKING FUN AT ALL... NOT AT ALL... I WAS JUST TAGGING ONTO THIS GREAT THREAD WHILE AT THE SAME TIME WONDERING IF IT WASN'T SOME KIND OF RECORD. IF NOT... THEN I SHOW MY IGNORANCE, BECAUSE I DIDN'T KNOW THAT THESE RIFLES SHOOT THAT WELL.... SORRY.... MY BAD.
 
Last edited:
Now that this bullet has been around a few months has any one put enough down range to have a good idea how they hold vertical at 1K?
 
Now that this bullet has been around a few months has any one put enough down range to have a good idea how they hold vertical at 1K?


A friend shot them in a monthly LR match last fall in a 260 running right at 2900 fps. I believe he was using H4350. His verticle was excellent. I’ll be testing them at 1k in Feb for at least two relays in a 260AI. Will report back when completed.
 
You have a good eye. Yes it is....I have been testing an AI version for a friend/GS/competitor. I am having too much hard bolt lift at moment to say anything definitive,

View attachment 1026513
I have been shooting the 6.5 WSSM since 2009 and have not found a cure for the hard bolt lift!! Doesn't matter weather I run 43 H4831 or 49 with 140.....bolt lift is the same.....H A R D !!!

LOVE the cartridge....HATE the bolt lift!! If you find a solution I would love to hear about it!!

Tod
 
Info Overload !! What is the difference between RL-22 and RL-23 ? My old 6.5-06 data had RL-22 as a top powder, along with H4831. - thanks !! Burn rate, temp sensitivity, density . . .
 
I have been shooting the 6.5 WSSM since 2009 and have not found a cure for the hard bolt lift!! Doesn't matter weather I run 43 H4831 or 49 with 140.....bolt lift is the same.....H A R D !!!

LOVE the cartridge....HATE the bolt lift!! If you find a solution I would love to hear about it!!

Tod

Hey Tod. I have a 6.5 WSSM for my deer rifle and, like Drew, am trying a 6.5 WSSM Ackley in an F-Class rifle. I don’t have an answer, because I don’t know, but I haven’t experienced any hard bolt lift on either, unless I’m into a max charge. My deer rifle is a 8.5-twist shooting 140 VLD Hunting bullets. I resize cases with a Redding F/L bushing die for the straight version. I put a 7.25-twist on my F-Class rifle and I’m shooting 155 gr. Cauterucio bullets in that one. Just starting load development with formed cases. I resize those cases with a Whidden custom die set up for the expander buttons. Drew was using my die and had hard bolt lift and experienced really high pressure with loads below where I started with. Maybe he’ll chime in again, but he may have even had his barrel chambered up with my reamer also. I dunno. Make heads or tails out of all that.
 
Hey Tod. I have a 6.5 WSSM for my deer rifle and, like Drew, am trying a 6.5 WSSM Ackley in an F-Class rifle. I don’t have an answer, because I don’t know, but I haven’t experienced any hard bolt lift on either, unless I’m into a max charge. My deer rifle is a 8.5-twist shooting 140 VLD Hunting bullets. I resize cases with a Redding F/L bushing die for the straight version. I put a 7.25-twist on my F-Class rifle and I’m shooting 155 gr. Cauterucio bullets in that one. Just starting load development with formed cases. I resize those cases with a Whidden custom die set up for the expander buttons. Drew was using my die and had hard bolt lift and experienced really high pressure with loads below where I started with. Maybe he’ll chime in again, but he may have even had his barrel chambered up with my reamer also. I dunno. Make heads or tails out of all that.


All true. And yes, using your dies and barrel chambered with your reamer, still pressure. Some differences are the action (mines a Rem700), the twist (1:8), the bolt (a PTG), and the brass (mine came from Winchester's 25wssm from this summer's run and I believe you started with 243wssm), just to name a few. Wouldn't think that any of those could matter, but I did have an exchange with a fella who provided a logical reason for a nonmagnum action giving my problem. Drew
 
Here’s a new wrinkle. I am a HP Silhouette shooter and also a close associate with Sierra Bullets.
I recently built a 6.5 X 47 and wanted to use the 150’s for my ram loads. I built my gun on a Tikka T3 Forest action/stock. Lilia makes a barrel contoured for this configuration, but I had to get a 1-7 twist. The ballistic guys at Sierra assured me that twist would shoot all weights of bullets.
They were right! I have worked up loads for 107 TMK, 130 TMK, and the 150 MK’s. They all shoot well, and the 150 really shines.
With H4350 I chronographed a group at 2832 average, extreme spread of 6 FPS, and a SD of 1.
I can’t wait to thump some rams with these bad boys.

Al Foust
 
Long answer: I think FrankG is probably using the Miller SI rule at 60 F and standard pressure at sea level and assuming a 1.5" bullet, which I saw posted by "Fast14riot" in thread "New Sierra 6.5 mm 150 gr Match King" on the main forum board today. When I do that, I get Miller SI of 1.44 for 1:8 twist, so I think Frank is calculating minimum twist rate for a 1.4 corrected Miller SI. In recent work, Litz said some improved results can be achieved by stabilizing up to a 1.5 Miller SI. My calculations show a 1.53 corrected Miller SI from a 1:7.75 barrel.

After looking at other similarly-low form factor 6.5 mm bullet data especially 140 and 147 ELD Match bullets, I am skeptical that 1.5 is the right bullet OAL. I think the correct OAL for the SMK may be closer to 1.45" instead of 1.5". If the bullet is indeed something closer to 1.45", then Miller SI at 1:8 twist is 1.59, and it is 1.50 with a 1:8.25 twist.

Short answer: At 3000 fps, if bullet is 1.5" long you may want a 7.75 or faster twist. If bullet is 1.45" long, then 8.25 or faster will be good.

Rarely do I use the Miller SI. I have a graph and formula that the Army made years ago.
 
Hi Tod

Assuming the load pressures are within reason, then check the inside diameter of the recess on the bolt against the brass diameter. I had a Barnard with hard bolt lift with a 300 WSM and it finally turned out the bolt recess was machined too small and the brass would bind up.
 

Upgrades & Donations

This Forum's expenses are primarily paid by member contributions. You can upgrade your Forum membership in seconds. Gold and Silver members get unlimited FREE classifieds for one year. Gold members can upload custom avatars.


Click Upgrade Membership Button ABOVE to get Gold or Silver Status.

You can also donate any amount, large or small, with the button below. Include your Forum Name in the PayPal Notes field.


To DONATE by CHECK, or make a recurring donation, CLICK HERE to learn how.

Forum statistics

Threads
165,841
Messages
2,204,682
Members
79,160
Latest member
Zardek
Back
Top