Hi All,
I tried a new load for 7mm RM Yesterday. Barnes 160gr TSX, Somchem S365 Powder (similar to IMR 4350), Fed215 primers and Norma brass.

Load # Load gr Velocity Ave Vel

58.5 2731
1 58.5 2719 2730
58.5 2740

59.0 2691
2 59.0 2695 2696
59.0 2701

59.6 2760
3 59.6 2770 2765
59.6 2765

Please explain why load 2 produced so much less velocity than load 1 & 3 (load 3 is obvious, but why less than load 1, velocity was very consistent though). All produced ± 1 MOA groups. In fact load 2 had the best grouping.

Cheers
Johan

Not unusual to see a "flat spot" when making
fine adjustments at near max pressure.

If you have any in that group of reloads i would tear one down and double check the weight.
Dave

A half to a grain of powder at the weight.

I wouldn't expect to see much differants and there isn't.

25 to 30fps isn't that much less vel.

I shoot the best one for accuracy and go with that.

I've seem this too. Don't know why it occasionally happens.

All the loads have very narrow extreme spreads. I agree with other forum member that it might be a flat spot. Going beyond your loads above, could go to eratic spreads. I would stick with the most stable and accurate one.

I assume all three loads were seated to the same depth?

quote:

Originally posted by JGRaider:
I assume all three loads were seated to the same depth?

Yes all to the same length. I have rarely a need to play with seating depth. Maybe when I would like to squeeze the last 1/4" I'll do it. But all my loads are between 1/2 -1", for hunting sufficient for me!


Cheers
Johan

[QUOTE]Originally posted by hivelosity:
If you have any in that group of reloads i would tear one down and double check the weight.
Dave[/QUOTE

Does anyone keep a "sample" of each load for reference. Maybe not a bad idea - at least until loads are tested. If anything goes wrong at least there'll be something to check! A thought I might consider.

Cheers
Johan

quote:

Does anyone keep a "sample" of each load for reference. Maybe not a bad idea - at least until loads are tested. If anything goes wrong at least there'll be something to check! A thought I might consider

Nope. Can't remember ever needing it.

As to the original question I've seen it. Only a couple times in 100s of load developments. I never found anything above that point if I remember correctly. I remember on a REAL OVERBORE wildcat the velocity dropped with a couple increases.

The challenge would be to load another batch at that weight and see what happens. it could be the best node.
Dave

Could the powder charge (or labels) for Load 1 and Load 2 actually been reversed?

Shoot larger shot strings and I'm sure it will work out. Sometimes with small samplings the average speed is skewed.

quote:

Originally posted by hivelosity:
The challenge would be to load another batch at that weight and see what happens. it could be the best node.
Dave

I think that's what I'll do. All three groups' average point of impact was very close, less than an inch. Even whith the slight drop in velocity.

Cheers
Johan

I find this strange - my friend here in NZ is also having difficulty with book loads achieving higher velocities. I get 3000 fps in my 280 Ack Imp with 160 gr Accubonds & Nosler book loads using N560.

My friend would be real keen on reliable safe loads for the 7mm Rem Mag that give 3000 fps with 160 gr accubond or 162 gr Amx / SST.