175gr Sierra HPBT

[STI_1911_Guy]

Hello,
I have been doing some research lately and i am currentl running the 168gr sierra hpbt @2755. I have been looking into the 175 and the best i have seen people driving them too is about 2700 so if i can get it to that then i will only be at 1268 fps @1000 compared to my current load @1222. Now it seems most people agree that 175 is better but does 40fps really make the difference?? The load i am currently shooting has done well for me out to 850 but i am starting to shoot farther and want to make sure i am not just making expensive noise. I have read about berger 155 and various others but these seem to shoot the best in my rifle and i would like to stick with them. (all figures were from viper vortex LBRC except the 168 gr which was actual data )

 

[LocoGringo]

Re: 175gr Sierra HPBT

Need more info...what's the twist rate on your barrel and the length? The 175 has a better ballistic coefficient than the 168 (resists wind better), so it's not just about velocity down range. Getting beyond 600, that can make a difference.

The reason I ask about twist rate is, generally, a 11.25 to 10 twist favors the 175 over the 168. I've heard (no personal experience) that the 168 begins to wobble when getting to extreme ranges for a .308. All of those reasons are why I chose to go with the 175 rather than the 168. I'm practicing and tuning to try to shoot consistently a 9 ring or better on an "F" class target at 1000. Currently going through load development. Good luck.

 

[Joop]

Re: 175gr Sierra HPBT

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: LocoGringo</div><div class="ubbcode-body"> The 175 has a better ballistic coefficient than the 168 (resists wind better), so it's not just about velocity down range. Getting beyond 600, that can make a difference.</div></div>
^This!^

Most .308 shooters will have similar results. For me and my rifle, I find that 700 yards is about the max range that I can be consistent with a 168 and if there's wind (when isn't there?) things become even more difficult. The 175gr range of bullets will help in this department. I'll take a slightly slower bullet that bucks wind better over a faster, lighter bullet that's blown off course more easily. Also, experiment with different bullets and don't be stuck on Sierra when other options might work better. A friend has the same rifle as I do (Savage 10FP) and his likes Sierras, where mine does better with The Hornady 178 grain A-Max. The difference is minimal, but it's there and when I'm trying to get the best out of the rifle, I'll take whatever it is that works, period (even when my buddy keeps telling me I should stick with Sierra!

) .

 

[CrawDad338]

Re: 175gr Sierra HPBT

Gravity/range is a constant and very easy to adjust for.. wind is the butt kicker, because of this 175s all day long @ 1k. BTW the Sierra 168s catastrophically fail/tumble once they go subsonic, the 175s don't.

Litz G7s
178 Hornady HPBT 0.257
175 SMK 0.243

 

[HarryBallz2029]

Re: 175gr Sierra HPBT

As of right now I am testing 4 different bullets in my 1-10" Savage 10 FCP 308. 175 SMK, 175 Barnes Match Burner, 178 Amax and 178 Hornady BTHP. Alot of people prefer the SMK for some reason and dont get me wrong it has obviously proven itself, but personally I am quite curious to see how the evenly priced box of 175 gr Match Burners from Barnes will stack up against the 175 gr SMK. 175 SMK BC = @ .502 the 175 Match Burner BC = .521, Just for comparison sake the Berger 175 gr LR BTHP is only .515. The Match Burner so far has a good BC going by there site of course. The bullet is a bit longer then a SMK too. I seat my 175 SMKs @ 2.828" while I just loaded 50 175 gr Match Burners @ 2.890" and they fit great in the gun. With that said as someone said above test all your options in the LR dept.

 

[longebow]

Re: 175gr Sierra HPBT

"A lot of folks prefer the SMK" because of their excellent performance at magazine length (generally "shorter" than single loading depth that is determined by a tool like the stoney point. This tolerance to seating depth is due to their tangent ogive profile--they are less "finicky" to seating depth variations. Sierra bullets are sold in bulk, generally easy to find, and have the reputation as an industry standard. I can dial my Redding competition die to my standard load setting, and the new box of Sierras will mike out as the previous lot. Other bullets (especially with the secant ogive or "vld" profile are MUCH more particular to seating depth, and generally perform better when just off the lands (0.010" jump). When loaded to these lengths, they generally exceed the usable magazine length. According to my mentor Hook Boutin of Georgia, he related that Mike Walker later lamented making the R700 magazine just over 2.80...