Tried a couple loads in my standard .260.
Best accuracy with a H4350 load at 2799fps. This was the highest load I tested and could be increased to about 2850 since I had no case head expansion.
R17 gave about 75-100 additional velocity with no case head expansion but accuracy was poor. Could get 2875-2900 if I could find an accurate load. All loads in a 30" Krieger with 0.165 throat and 0.065 lead in.
Wish I could get the R17 to shoot.
Anyone have any suggestions?
Thanks
Bill
Alliant claims they are close but not exact swaps so drop a grain and a half or two to start.How does burn rate of r16 compare with r17?
RL 16 is very close to H4350. I am running it in three cartridges; 6 Dasher, 260AI & 284 Win. Very Temp stable.How does burn rate of r16 compare with r17?
This, RL16 is closer to H4350 than anything else, but ever so slightly faster. Good stuff!RL 16 is very close to H4350. I am running it in three cartridges; 6 Dasher, 260AI & 284 Win. Very Temp stable.
Well Ben what is going to be the perfect caliber for this bullet? Just need around 2950fps and we will have one very enjoyable gun to shoot.I don't know if an 8 will stabilize. However, in a 6.5 x 284 this bullet with either H1000, RL-26 or Retumbo should easily get to 3000.. Additionally, with those powders you should get 14-1500 rounds of barrel life! This ought to be a real 1000 yard F-Class champ>>>>>IF it shoots!!
Good Morning Tom! My pick is the 6.5 x 284. However, the 6.5 SAUM should do everything the 6.5 x 284 will with 100+ additional f.p.s. In either event, the very HIGH B.C. of that bullet, combined with some good speed, will make this bullet a game-changer in my opinion.. As soon as some shooters start to win matches, it will catch on AND catch on like wildfire! Compared to a 7mm 180+ bullet, this will have very noticeably LESS torque and recoil. These attributes alone will help considerably.. Let's wait and see!Well Ben what is going to be the perfect caliber for this bullet? Just need around 2950fps and we will have one very enjoyable gun to shoot.![]()
I did some bench testing yesterday with the 150 SMK in my 260 Remington with a 1 in 8 26 inch barrel. I got good accuracy with 41.0 grains of H4350 but above that the groups really opened up. The velocity with the 41.0 grains of H4350 was about 100 fps lower than my pet load of 142 SMK with 42.2 grains of H4350 so there is no reason for further consideration of the 150 SMK in the 260 Remington in my barrel configuration. This was no surprise and what your probably would have guessed but I wanted to know for sure. I think the 150 SMK will be a great bullet in the proper cartridge and barrel configuration so I am not being negative at all toward this bulletI was wondering how far the 150 SMK would stick down into the case of my 260 Remington as compared to the 142 SMK. I made the measurement and as it turns out the dimension is the same for both bullets. I have a standard 260 chamber so the 142 SMK sticks into the case past the neck but this has not seemed to me to have been a problem since I get good accuracy and velocity with the 142 SMK in this configuration. So I plan to load the 150 SMK with the same load as I have been shooting with the 142 SMK for 1000 yard competition and see how it does. I will start with accuracy and velocity testing at 100 yards and will have my 142 SMK data for comparison.
What is the twist and length of your barrel?I just thought I would provide some data for anyone who cares. My Tikka SL 6.5 Creedmoor is pushing the 150 SMK 2780fps with great accuracy(<.5moa) and low ES with RL26. I am using crappy Hornady brass and BR2s. This is with the boat tail junction seated at the NSJ so it is quit a bit longer than 2.8". The accuracy node in my barrel is about .5 grains under the beginning of a change in bolt lift. Primers are perfect and zero ejector marks. I will start testing RL26 for temp stability as I have heard mixed reviews.
Frank,According to my numbers at 3000fps. a 1-8.184 would be the min. twist required.
Don't forget about temperatures, elevation, humidity etc....all play a part.
If you have a true 8 twist barrel they should fly for ya.
I'm doing a faster twist for my 6.5 Creedmoor.
Later, Frank
Bartlein Barrels
What is the twist and length of your barrel?
Is that a WSSM case? I have a few 6.5 WSSMs now, or 6.5 Gertrude’s as I call them. They make a good low recoil practice round for my magnum actions, with decent ballistics as well. I will be trying the 150s in my 8” twist this summer. (I suspect the bullet will not be stable enough to shoot in 8” twist in winter)Whaaaattt? I thought if you could get the bullet to fit in a 308 Win case, it was all fair.....JK
This is a "new" cartridge that my GS is having me test...stay tuned. Just fireforming at moment. Awaiting Custom Whidden FL dies to actually test the potential. I'm voting for the 6.5Diggler as a potential name.
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