100 yards, 3 shot groups....
300 yards, same loads, two "ladder" style targets with velocities marked on targets....
Target 1
Target 2
Individual velocities in notes....
The 168 grn FGMM target for reference.....
Feedback on results IMR 4350/175 SMK 30-06, 24 inch 1:10 Douglas
- Thread starter pmclaine
- Start date
100 yards, 3 shot groups....
300 yards, same loads, two "ladder" style targets with velocities marked on targets....
Target 1
Target 2
Individual velocities in notes....
The 168 grn FGMM target for reference.....
Was the intent to run an OCW? If so, Why did you choose .5 grain increments?
Typically I’ll do OCW using in .3g increments in charge weight as it’s a nice balance of spacing but still tight enough to see a harmonic node(s), which from my experience is typically .7-9 grains wide over 3 groups where the center of the three rounds POI-wise is the same direction/distance relative to the POA.
Also, I wouldn’t recommend you do an OCW with a magnetospeed attached since it may influence your results and muddy the waters when initially trying to identify the node(s).
Typically I’ll do OCW using in .3g increments in charge weight as it’s a nice balance of spacing but still tight enough to see a harmonic node(s), which from my experience is typically .7-9 grains wide over 3 groups where the center of the three rounds POI-wise is the same direction/distance relative to the POA.
Also, I wouldn’t recommend you do an OCW with a magnetospeed attached since it may influence your results and muddy the waters when initially trying to identify the node(s).
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Testing at 100 yards was without the Mspeed.
When I shoot with Mspeed it tends to group well but consistently .5" high at 100.
I get it though it interferes with harmonics.
I was surprised by the speeds I was getting with little signs of pressure.
My preshooting impression was 2550 to 2650 was where I would find nirvana - shots 1 through 4 indicate that may be a good hunch.
Wish I had of started lower.
Velocity fans will disagree with good reason.
@MontanaMarine had a lot of good 30-06 data I would lurk on.
Im not looking to beat the rifle or myself up. Rarely will I get to shoot beyond 300 but I intend to make an effort to get 1000 with this rifle if the blocks will get me there.
When I shoot with Mspeed it tends to group well but consistently .5" high at 100.
I get it though it interferes with harmonics.
I was surprised by the speeds I was getting with little signs of pressure.
My preshooting impression was 2550 to 2650 was where I would find nirvana - shots 1 through 4 indicate that may be a good hunch.
Wish I had of started lower.
Velocity fans will disagree with good reason.
@MontanaMarine had a lot of good 30-06 data I would lurk on.
Im not looking to beat the rifle or myself up. Rarely will I get to shoot beyond 300 but I intend to make an effort to get 1000 with this rifle if the blocks will get me there.
Not a strict OCW.....Ive done the .3 increments before and at the end of it I feel like Ive eroded so much headspace that my results have changed.
My 100 yard groups didnt expose any great issues. On that data alone I would go for 55.5 and the one hole group it made.
But....
At 300 getting velocity numbers shots 1-4 are close to MOA and they are in that sweet spot for 175 SMKs velocity wise.
Eroded headspace? Do you mean to say “throat”?
I don’t see a truely stable node in that first image of the 100 yard groups but because you did .5 it isn’t likely I would simply because your increments are too coarse
here is my AXMC 300 Norma OCW using the 215 Berger. Look at 81.9, 82.2 and 82.5. What do they all have in common?
At this stage of the process I’m only looking for ttheee things: muzzle velocity, impact patterns and pressure. I’m not concerned about group size or sd/es at this initial stage.
Spotting your pressure threshold with a given set of components: measure your unfired rounds on the case just above the extractor groove. Then measure again after firing and note the expansion. Anything above .0005 indicates pressure. Use a 1” micrometer with ball anvils for beat results but a good set of calipers will also work.
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You have consistent POI from 55.5-56.5 and also from 53.5-54 and possibly 54.5 would be in the same dispersion. When over layed the groups would be a little over 1 MOA for the three charge weights. I would run OAL testing @54g or 56g if those didn't show any pressure.
In that case I’d be looking around 3&4. That’s where she wants to shoot. I’d expand the range by bookending those loads by a tenth or two and splitting them. So five rounds of five different loads total. I’d shoot those 25 rounds round robin and find the middle of the sweet spot. I would verify and tune seating depth using the two closest to the center.
Today I checked out the sub 52.5 powder range, an area I estimate to be between 2550 -2650 velocity based off my previous data.
I like it....
Tomorrow I will see what happens in the 54 to 55.5 +/- range.
I like it....
Tomorrow I will see what happens in the 54 to 55.5 +/- range.
Velocity is not always happiness...
Gonna have to get some Sig Sauer 175 ammo velocities though because that shit delivers...yesterday and today, 5 round groups.
I think from yesterday 52.2 is going to be my load...
Gonna have to get some Sig Sauer 175 ammo velocities though because that shit delivers...yesterday and today, 5 round groups.
I think from yesterday 52.2 is going to be my load...
