CB load development

[malpaismike]

Hello the camp! The question: does anyone have skinny on load development at short range, eg 25 yd? 25 yd is nominal range for getting scope on paper; I could do this in my yard. We've all read the gunrags about 100yd, 3/5/10-shot groups for record, etc. When I left Mesa, I pitched gunrags from late-60s up--in case of AR, only had 5 missing issues since '72. That said, I don't recall info on short-range tests. It figures that even a 4" group at 100yd is 1" at 25, making choices iffy. I hypothesize acceptance criteria, for starting loads, if at least 3 of 5 rd are touching. Since I'm talking .30-40Krag and .38-55Win, if I got touching rounds, I then load a series and head for the range, in my case about 20mi. Is this a practical bent? Appreciate your input. thxnregards mm

Mike Webb
Sierra Vista, AZ

[geargnasher]

For initial workup, I see no errors in you logic. If you can shoot 1/4" on centers at 25 you should, theoretically, still be MOA. Of course there are those rare instances where a load will fall apart past 50 yards but shoot great at less, but for the most 25 yards should be good enough to be close at 100. Plus, you can chronograph your loads at home at your leisure, taking time to set everything up carefully so you don't shoot your chrony!

Gear

[kir_kenix]

You may even find that a group will shoot better at 100 or 200 yards then it does at 25 however. I set my 600 yd benchrest rifle up to shoot thru a series of large cardboard cutouts at 100, 200, and finally 400 yards (furthest out at my home range) to get reliable drop/group/wind-dope info before declaring a load keeper. Often times a given load will shoot smaller "moa group" at 400 then 100. I've had several different ppl tell me this has to do with the yaw of the bullet as it leaves the barrel. I suppose that this would even be more significant at 25 yards.

That being said, I think you should go ahead and try 25 yard load development and not worry too much about it. I would think that long, skinny 6mm and 6.5 bullets would be more affected by yaw then the big boolits ur talking about shooting.

[HangFireW8]

Hello the camp! The question: does anyone have skinny on load development at short range, eg 25 yd?

I have a M/L that is dead-on bullseye accurate at 25 yards, poor at 50 yards and all over the place at 100 yards, with a 60 charge. Bringing up the charge to 80 pulls groups together at the longer distances.

So, it is possible to have a barely stabilized bullet just "lose it" right after the 25 yard target.

Other than that, no reason not to start at 25. If you can't get it right at 25Y, the further ranges are not going to look good, either.

-HF

[NickSS]

I have shot many groups with cast bullets at 25 yards and 50 yards in my back yard range. Generally if they are shooting good at 25 they will be shooting as good or better at 100 yards.

[dromia]

25 yrds is good.

I shoot at 25yrds two weeks out of four on a barrack range and use this to try out loads and chronograph, no need to stop details to check targets, just hunker down and shoot.

This helps me winnow down the loads to those with the most potential which I can load up for testing on the other two Saturdays of the month when I can shoot back to 600yrds and the three times a year when I get back to 1200 yrds.

So the 25yrd shooting is crucial part of my load development regime and saves me a lot of range time.

Occasionally you will get a wobbler that doesn't do well at longer ranges despite the 25 yrd promise, but they are rare and the reason is usually clear and half expected.

[malpaismike]

Much obliged. I'll let you know how it turns out. thxnregards mw