Ladder Test Help?

[Willys46]

I tried a ladder test today with new 7 RUM. I was using Retumbo starting load at 88gr working up to 94 gr by .4 at a time.
Do you typically do this test at 300 yrds? Problem was that most the shots went into two groups with very little vertical spread. Here are the results:

1 3024
2 3003
3 3004
4 3083
5 3085
6 3084
7 3107
8 3108
9 3153
10 3143
11 3182
12 3200
13 ####
14 3218
15 3270
16 3269

I think shot 13 did not register. I was thinking shots 4,5,6 and 12,13,14. What would you suggest?

Thanks for your input!

[Crosseyed]

It seems to me that 300 yards is stretching it for a ladder test (just my opinion). The goal is to determine the most accurate load and I feel that at that range, there are too many other variables present. I would shoot the ladder at 100 (what I've always done), pick a load, and then take it out to 300 and see what it does. Just my opinion.

[AJ Peacock]

[ QUOTE ]

I think shot 13 did not register. I was thinking shots 4,5,6 and 12,13,14. What would you suggest?

Thanks for your input!

[/ QUOTE ]

I agree, 4,5,6 and 12,13,14 Depending on what I was wanting out of the load, I'd either try a couple groups with #5 or #13 to see if one was near what I was looking for. If you are looking for a load around 3200fps, then try 3-4 rounds each side of #13 (.1gr per step) to figure out exactly where the node is. Then pick the most consistent part of the node for your load.

What bullet are you shooting?

Don

[abinok]

based only on velocities, I agree as well.

Oh, and not only is 300 yards not "streaching it" for a ladder... its just getting warmed up!

I shoot almost all of mine at 300, and verify at 400... even the old marlin lever gun I loaded for the other day... that will probably never be fired at hair by its owner past 100yds.

[Willys46]

Sorry I left out the details.

7RUM Serndero, only the trigger has been touched up.
160 Accubond.

Thanks for the Advice, I will load some around #13. I started having stiff bolt lifts at #15 and #16.
I will get back with results of 300yr test.

Off to the range.

[AJ Peacock]

[ QUOTE ]
Sorry I left out the details.

7RUM Serndero, only the trigger has been touched up.
160 Accubond.

Thanks for the Advice, I will load some around #13. I started having stiff bolt lifts at #15 and #16.
I will get back with results of 300yr test.

Off to the range.

[/ QUOTE ]

Let us know how they turn out.

Good Luck,

Don

[Willys46]

Back From the range with mixed results. Here us the data:

Test One FPS
1 89 2974
2 89.1 3093
3 89.2 3105
4 89.3 3130
5 89.4 3103
6 89.5 3125




Test Two FPS
1 92.6 3210
2 92.7 3235
3 92.8 3226
4 92.9 3245
5 93 3247
6 93.1 3252

Just for giggles I shot a 3 shot group at 300yrds with the 98.2 load. 1.16" or .38 MOA. Not that bad of group but the velocity was---3266, 3248, and 3223. Verticle was great, I misses a wind call!

I think I might try the 93 grain load and see if the velocity spread shrinks. I thought that the velocity spread was large (43 FPS).

Thanks for the feed back and Help
Willys46