7wsm...headaches

[Jpatnode]

hi Everyone...Im kinda new to the long range game but have been shooting small cal. tourney's for 2 seasons. I have used 6mmbr.com heavily but have never been big on posting. i just finished building my first gun [ trued M70 action- krieger 1:9.5 pipe-mcmillian F class stock, timney trigger]..well after a few months of research i decided to go with the 7wsm rather than the .308 seems to be a aging round. then after building my rig i realized that ammo is virtually non-existant,lol I tried a few loads from the site with minimal results. I can shoot about equal moa outta my .243 howa axiom. its seems that after about 700y it falls on its face...which is the whole reason i went with 7wsm rather than the .308 my current load is 52grains of RL19-175 sierra MK's, turned Win brass, fed210 primers. they chrony at around 3050 but perform about the same as federal premium hp's, did i get the wrong twist? ANY input on a good started round would be MUCH appreciated!!!

 

[tillroot1]

A little more on your chamber would help, but I would look into trying the 168 bergers first! Then the 162 A-max bullets, your twist rate may be too slow. How long is your barrel? I think that Bolo that Lynn is talking about shoots the 7mmRemsaum
not the wsm. He does very good with his and could offer some help as well. good luck, Ron Tilley

 

[Jeffvn]

Steve - Bolo - shoots the 7SAUM, not the 7WSM, but his insight will also be useful here.

I shoot the 7WSM for F-Class, and most everyone that I know who does has a 9 twist - some have 8.5. We shoot the Sierra 175, 189 Cauterucio, or Berger 180s. I think you are probably on the edge of stability with the Sierra 175, but if your holes are round, then your running them fast enough to keep it straight. I suspect that running them that fast may potentially be leading to your problem,but Bolo runs the Berger 180s at 3100 of something like that) so holding velocity below 3K is not an absolute. I do not recall meeting anyone else running RL-19 in combination with the 175 SMKs or Berger 180s, as most run H1000, Retumbo, H4831, RL-25, RL-22.

I sugggest you look at some of the load combinations suggested on the .284 page on the main page for 6mmbr.com.

I agree that you may be more suceessful with your twist rate by using the Berger 168s or 162 AMAX. Keep us informed about your progress.


JeffVN

 

[beartrack]

I'm kind of curious how it REALLY shoots. As you've worked up these loads. What's a 300 YD 5shot group like? How does that compare to what you describe as "falling on its face" at 700 YD? If RL-19 isn't bringing you exceptional groups out of a rifle like that at the near range, maybe it's time to try another powder.

 

[Bolo]

Jpatnode, your twist rate for the 175s is a little slow, but I think that you might want to chrono your loads with a more accurate chronpgraph.I doubt that 52 grains of R19 will be 3050fps. Also compare your velocities against the Federal premium. I believe the Federal premiun uses the SMK.
With R19. Shoot the 168 SMKs. Should work well for your twist rate and the BCs are better than published. The 162 AMAX is very accurrate but you get only slightly better performance than a 6.5/284 with alot more recoil.[R22 seems to be the powder for 160s]
Load density is is not that high with R19. Better powder choices for the 175s would be R25, H4831sc or 1000 or Retumbo. I like R25 but got to keep my ammo warm when it's cold.[Get unexplained verticle]. The H4831sc is not so temperature sensitive, but my tubes like the R25 better. Never tried the other 2 but they should work just fine.

 

[Magical_Merlin]

I use H1000. I have a 1:9 twist that I shoot the 180 Bergers. Shoots very well.

 

[Jeffvn]

I used to use RL-25 - like Bolo - but the summer heat in Las Vegas, forced me to change to H1000. It is not as fast, but has a nice tight ES and SD, which is critical from 1,000 yards.

Bolo - Im not sure it was the powder, I'm thinking it was the regular russan primers not liking the cold weather; I suspect if you were using Fed 215M - you would not have had the erratic verticle. Either way, "keeping your pills warm" proved to be the ticket to reducing the vertical.

JeffVN

 

[Jpatnode]

thanks guys = sorry for the long delay on the re-post,Deer then muzzleloader season)much better response than expected! im runnin a 28" btw. think im gonna try the 180bergers/h1000 and work from there what you guys runnin for powder weights? when i say " fallin on its face" its just sheer drop- im dailing more vertical with my wsm than my .308

 

[Jpatnode]

also what you guys runnin for powder weights? im from Green bay,WI btw....usually temps are between 65-80 for shooting season

 

[Jeffvn]

I'm using a Long-throated chamber specifically cut for the Berger 180s and use 66.3 grains of H1000 with Fed. Gold Medal Match Magnum primers,215M). She runs 2,940 in my 28" Kreiger. and does really well for me. I also used 65.00 of RL-25 for the same rifle with the 180 Bergers and it gave me excellent results, but was a touch too high pressure for the Las Vegas summers.

JeffVN

 

[Jpatnode]

thanks again! i picked some 180vlds gonna try out this load. i did notice though these are some long ass pills! what ya runnin for a total length? im runnin 2.75 with the sierra's but these seem quite a bit longer. seated same depth there at 2.93 should should i sink em further or is that about right? Not gonna try em till spring though cold finally hit hard-18 below zero today....sorry for the ton of questions...kinda new to the whole precision game