Tikka 7 SAUM project

I wouldnt touch the gun until you've done a seating depth test first. Do a seating depth test by picking your charge weight and load your charge weight in all the cases you want to test. Seat bullets over a good spread in either .003 or .005 increments and shoot for groups. My charge weight ladder test looked like yours until I did my seating depth test. I had to do a course seating depth test to find the ballpark I wanted to play in, then I did a fine test. I am going to do a super fine test in .001 increments around the obvious winners...for science... but I don't think it is truly necessary. I also have a different chanber than the chamber oroof uses, but it is a 7 saum shooting the 180 berger hybrid. I thunk you would also get better results if instead of measuring COAL you measured CBTO. Its more accurate for repeatable performance bullut to bullet. After trying all that, if you get nowhere, then I would think about bedding it.
 

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If it was me I'd do a good clean then shoot 7-10
Foulers and load 62.5 h1000 and see if it groups right there.
FYI:
My son's 24" Proof 7 SAUM has only 40-50 down and it shoots much better after cleaning... especially during load development while switching powders.
 
FYI:
My son's 24" Proof 7 SAUM has only 40-50 down and it shoots much better after cleaning... especially during load development while switching powders.
The rifles been cleaned, I'm switching to WLRM primers and shooting another ladder with H1000 but in .3 increments. Everything is loaded already, I annealed the brass too so maybe that will help.

I've had good luck with those primers in my 300wsm. I'm not going to shoot it till after I've bedded it and I can't do that till next weekend.
 
You should definitely bed your stock.

My 7SAUM is the Tikka proof 24" prefit, the same barrel. It shoots best with the following combos:
162 eldm H4831sc 2900fps .010 jump
180 berger HVLD H4831sc 2850fps .100 jump
195 Berger EOL H1000 2770fps .020 jump

ADG brass and CCI200 primers.

Mine really sped up in the 150-200 round count.

Not sure if this helps you at all, just some data from a very similar setup.
 
Bedding is complete, it turned out okay I'd say 7 out of 10. First time bedding a Tikka, I will do it differently next time. Anyways I shot another ladder:
1 62.5 2855fps
2 62.8 2859fps
3 63.1 2854fps
4 63.4 *Wouldn't chamber
5 63.7 2855fps
6 64 *Wouldn't chamber
7 64.3 2919fps
8 64.6 2928 (sticky bolt)


I bump sized the brass this time and evidently not quite far enough back hence the two rounds that wouldn't chamber. I'm happy with the node between shots 1 and 3 and I think I'll shoot that. Seems to be a nice mild load.
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Bedding is complete, it turned out okay I'd say 7 out of 10. First time bedding a Tikka, I will do it differently next time. Anyways I shot another ladder:
1 62.5 2855fps
2 62.8 2859fps
3 63.1 2854fps
4 63.4 *Wouldn't chamber
5 63.7 2855fps
6 64 *Wouldn't chamber
7 64.3 2919fps
8 64.6 2928 (sticky bolt)


I bump sized the brass this time and evidently not quite far enough back hence the two rounds that wouldn't chamber. I'm happy with the node between shots 1 and 3 and I think I'll shoot that. Seems to be a nice mild load.
View attachment 401908View attachment 401909
Looking good!
My opinion.
I like that #1 load. I'd work up another group with that #1.
It's not showing any velocity increase up to load #5 so it keeps you away from pressure.
You can work up a bit after she breaks in and picks up speed.
 
Looking good!
My opinion.
I like that #1 load. I'd work up another group with that #1.
It's not showing any velocity increase up to load #5 so it keeps you away from pressure.
You can work up a bit after she breaks in and picks up speed.
I should have done #1 after recognizing your point. I loaded the rest of my rounds with the #2 load this afternoon. Opening day is next weekend and I'm out of time.
 
No problem.
#2 is close and a good start too.
If all pressure indicators seem fine, do a group with that load and if your numbers are acceptable...roll on through the hunting season with that.
From your data, this charge weight appears on the lower quadrant of the node so you shouldn't encounter pressure problems.
As mentioned earlier... it should speed up a bit and settle once you get 150 or so down the pipe and you can tweak and tune your load then if needed.

FYI...My son's exact barrel (Proof 24" 7 SAUM) has 40-50 rounds thru and is taking his best preliminary load of 150 Partitions through the hunting season before any further work as well.

Good luck!
 
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I should have done #1 after recognizing your point. I loaded the rest of my rounds with the #2 load this afternoon. Opening day is next weekend and I'm out of time.
Hello, there, fellow Montanan! I know exactly what you mean by running out of time. I was doing some load development with my .257 WBY ran into LabRadar issues (operator error, LOL!). I, too, have a 7MM SAUM that needs load development; thanks for sharing - I might have to use yours as a baseline.

Happy safe hunting. Good luck!

Ed
 
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