Any short cut tips on bullet seating depth

[223AI]

so when you do your load development you do 5 to 10 shots each powder charge and then 5 to ten shots each seat depth ? 3 shot groups are fine to scan for optimum powder charge and seat depth. then when you find those nodes fine tune with 5 shots.

If you're finding optimal weight and length with 3 shot groups what is there left to fine tune with a 5 shot group?

[ZAKDINGEL]

Im using big game in the .243 I don't use the 75grn vmax I found they weren't that good I now use 70grn serria blitzking with 40grn of powder seated to 2.617" but that's in my gun I found out that more powder made the group open up

[Eyefor]

Hi Lads.
243 hornady 75g v-max heads, done the powder weight testing arrived at 43.5 gn of Ramshot big game.
With a bullet seating depth of 2.640 im getting two shots within 1/2" with the third at 1 1/4" that is random -------suppose this needs more work ?
From 2.640 - 2.745 which is around the maximum length i can go while still keeping 6mm in the case neck there would be 22 setting at 5 thou, i dont fancy doing all them shots, can anyone suggest any ways to reduce this, ie with the 2.640 seating depth doing 1 1/4" group, does this suggest it just need 5-10 thou either side of this ----or doesn’t it work that way ? -------am i better starting at 2.745 and reducing by 5 thou until i hopefully get there.

Thanks for your help Dave (warbucks)

DEFINITELY load then length.

Its generally recognised that the powder is the first step followed by the distance from the lands.

My advice for a 'short cut' would be to use the OCW method whereby you start with a uniform distance from the lands ( I would suggest 40 thou back) for the weights of powder you have selected when using the 75 gr V max. If you move up in .3 gr increments you should find a node from the OCW target that is good and if you feel there could be improvement then stay with that powder weight but alter the distance from the lands to see if there is a change for the better.

A considerable time ago (and after a serious amount of frustration with one particular 22-250) I followed Mr Dicehorn's advice and finished up with a home brew that sat -137 thou off the lands that was simply fabulous.

Once you have found the load, make up 50 rounds at mid level OAL (as above, 40 thou) and then go to the range with your press and dies, fire five rounds, squeeze the next 5 rounds in 5 thou and repeat.

Stick with it. It is worth it.

PS (x2)

1. Batch weigh the v-max (some awful variations)

2. Ditch the v-max and switch to Sierra's

[zx10mike]

If you're finding optimal weight and length with 3 shot groups what is there left to fine tune with a 5 shot group?

well once your are close you will be down to the .2 of a grain powder and 1 tho seat depth change.not sue you would want to do that on every charge and seat over a wide margin.

[Parabuteo]

Nodes are based on more than OAL. It is to do with the points at which the barrel vibrates at the highest freq (so lowest amplitude). Node will depend on all sorts, barrel thickness, length, materal, charge, hold etc etc.

This is why people shoot a ladder test/load test, then fine tune with the OAL.