Smk 175 in .308
- Thread starter wboggs
- Start date
My accurate load with 175 gr. Sierra is:
LAPUA FF'ed BRASS W/LIGHT TURNED NECK CLEAN-UP
175 GR. SIERRA TMK 2.181 O M 2.954 COL T/L B S .426
POWDER H-VARGET 43.6 GR. PRIMER FED 210GM M
SEATED @ 2.161 O M 2.934 COL .020 OTL 09/06/21
11 1/4 Tw. BARREL
LAPUA FF'ed BRASS W/LIGHT TURNED NECK CLEAN-UP
175 GR. SIERRA TMK 2.181 O M 2.954 COL T/L B S .426
POWDER H-VARGET 43.6 GR. PRIMER FED 210GM M
SEATED @ 2.161 O M 2.934 COL .020 OTL 09/06/21
11 1/4 Tw. BARREL
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3Sigma
Silver $$ Contributor
On my savage, .010 off
On my Remington SPS Tactical, about .090 at 2.85" OAL. I can't touch the lands and fit in the mag.
Reality is rounds setup for either gun shoot within .5 MOA on both. Can optimize for slightly better (.4 moa 5 shot groups) on the savage, but past 600 yards it is moot as the wind is king.
175 SMK is a great bullet for a wide variety of chambers.
On my Remington SPS Tactical, about .090 at 2.85" OAL. I can't touch the lands and fit in the mag.
Reality is rounds setup for either gun shoot within .5 MOA on both. Can optimize for slightly better (.4 moa 5 shot groups) on the savage, but past 600 yards it is moot as the wind is king.
175 SMK is a great bullet for a wide variety of chambers.
Always like this bullet. Personal experience is 25 to 40 off of hard jam. My opinion is that the closer location in the 10 to 15 range is narrow and picky at times. Never had much need to go past that, but I am sure more locations exist.
0.020" in the lands and 0.020" jump. If either don't shoot, try a different bullet like any of the Berger 185 gr bullets.
But in all honesty, the 175 SMK doesn't really care that much and is not picky about distance to the lands.
Below freezing use any primer but CCI. Above freezing CCI BR2 (or BR4 for Palma brass) work great.
But in all honesty, the 175 SMK doesn't really care that much and is not picky about distance to the lands.
Below freezing use any primer but CCI. Above freezing CCI BR2 (or BR4 for Palma brass) work great.
wboggs
Gold $$ Contributor
P M Sent.
XTR
F-TR obssessed shooting junkie
someone once commented that the Sierra 2155 was shaped like a tugboat, the 175 was made in the same boatyard. My recollection is that it didn’t really matter where you seated it as long as it was consistent.
Shooting it to 1000 yds was another thing, it needed about 5 minutes more than a 185 to get there.
Shooting it to 1000 yds was another thing, it needed about 5 minutes more than a 185 to get there.
Let me make this point as I have before . . . different guns/barrels have different freebores. If I say .020 jump works well for me and the freebore in my gun is .245 and you set your cartridges to that same jump, but you have a freebore of .180, that's a .065 difference and your bullet will be deeper into your case by that much and producing significantly more pressure and likely will not perform as well. If you ask what COAL for a 175 SMK is that performs well, then you can take that COAL and know that it's going to be seated somewhat close to the same depth (knowing there's some variation in a bullets OAL) when you load them. You're more likely to get close to the same performance as the one you've copied even though the jump will be significant with this difference in freebore, as seating depth is a much bigger influence on performance than jump. Even going by someone's COAL, there could easily be a problem where what works in my longer freebore may not fit into yours.
With this understood, 175 SMK's COAL that has worked well for me has been at 2.886" (.020+" jump). I say "+" because the jump has been growing due to throat erosion, yet keeping with the 2.886" COAL I continue to get good results.
Note too that the powder one uses, like due to its burn rate, can render the benefits of a jump null.
PS: If you haven't already read the series of articles on jump here, it can be very enlightening:
More Bullet Jump Research!
This is the 4th article in a series on some new research on bullet jumps. Here is a recap of the pr...
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Nvcnvc
Gold $$ Contributor
That is a beautiful sight, Bill! Well done!
Hmmmm??? That could mean your COAL is anywhere from 2.790" to 2.998 or more depending on throat erosion???
WSnyder
Silver $$ Contributor
Throat erosion in a .308"??? It's one of the easiest cartridges out there on throats. How many shots do you think it would take to move it .200"??? Never seen anywhere near that much erosion in a .308 even over thousands of rounds.
LVLAaron
Gold $$ Contributor
Hmmmm??? That could mean your COAL is anywhere from 2.790" to 2.998 or more depending on throat erosion???
It's just a load I keep on the shelf for "any 308" they dont care a whole lot about jump. I don't chase lands with that load. It's what I consider my "factory ammo"
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