Sierra 168 TMK - distance from lands?

[Bob 964]

I have been anay from the forum for a while, so please forgive me if this question has been asked and answered. If it has, please direct me to the answer. Anyway,,,

I shoot an FN SPR A3G chambered in .308. I would like to know from those who are shooting the Sierra 168 TMK if this bullet performs better loaded closer to the lands or further from the lands. Thanks for considering my question.

Bob

 

[300ATT]

The Sierra SMK's are very forgiving and in my experience you do not need to be all that concerned. Load to 2.795" - 2.800" overall cartridge length and see what happens. 9 time out 10 it will just work.

 

[sandwarrior]

I have been anay from the forum for a while, so please forgive me if this question has been asked and answered. If it has, please direct me to the answer. Anyway,,,

I shoot an FN SPR A3G chambered in .308. I would like to know from those who are shooting the Sierra 168 TMK if this bullet performs better loaded closer to the lands or further from the lands. Thanks for considering my question.

Bob

As I have not loaded the 168 TMK's as of yet, what angle do they have on the boat-tail? It would best be compared as steeper or more shallow than a SMK 175. I'm just wondering if they changed that from the 168 SMK.

 

[Eric32]

the TMK's are completely different from the SMK's, the new 168gr TMK has a 9 degree boat tail, while the 168gr SMK has a 13 or 12 degree I can't remember 100% right now.

your going to have to do a seating depth test, I followed the Berger VLD test and ended up at .050 ish off @ 2740 fps

 

[sandwarrior]

the TMK's are completely different from the SMK's, the new 168gr TMK has a 9 degree boat tail, while the 168gr SMK has a 13 or 12 degree I can't remember 100% right now.

your going to have to do a seating depth test, I followed the Berger VLD test and ended up at .050 ish off @ 2740 fps

Eric32,

Thanks for that. It may be worth the while to go back and test 168's again. Seems to me I remember the SMK boatail being 13 deg.

 

[Eric32]

if you can get them to run well they are great bullets at a pretty reasonable recoil factor. In a 10 twist they retain all the BC at 12-13twist they lose some some, since they are so much longer than the SMK's