Weight sorting Primers!?

[Josh11]

Would like to have your input on this subject.

I'm not a bench rest shoot nor a professional, but I do try to keep everything the same as possible. I have a brick of Remington 7.5 primers and also CCI 450 primers. I shoot the CCI for best accuracy, but I wanted to save them for matches so I decided to try some loads with Remington 7.5. Many people weigh loads, bullets, brass ,ect,ect. I thought what if the primers weighed different if that would make a difference in es/sd and keep the velocity more consistent. This may not make a difference at 100 or even 300 yards, but what about 1000 this might help.

I started off by weighing Rem 7.5 primers. Out of 100 primers, 74 of them weighed 3.5 grains. 21 of them weighed 3.6 grains, and 5 weighed 3.7 grains.

The CCI 450 primers weighed 83 of them weighed 3.7 grains, 11 of them weighed 3.6 and 6 weighed 3.5.

I was not really surprised to find out that the CCI primers are more consistent in weight than the Rem 7.5 primers. This could be one of the reasons that most people get better es/sd out of the the 6br cases. But was surprised that the Remington 7.5 primers weighed less because it is believed by most that Remington 7.5 primers are hotter that most other primers.

I do not have a Chronograph but hopefully will shortly. I weighed these primers with a RCBS Charge Master, without the dispenser. If someone was to do this with a better scale, I'm sure it would be better. Will check and see what this does to groups groups at 600 yards soon.

 

[RonAKA]

I see that the CCI 450 primers are slightly taller than the Remington 7 1/2's, at least according to this link. Perhaps the reason for weighing more. Not sure of the ratio of weight of priming material to just the weight of the metal. But the metal may be quite a bit more, and minimizing the effect of different amounts of primer material.

http://www.jamescalhoon.com/primers_and_pressure.php

A lot have a go at weighing 22 rimfires and sorting by weight. I suspect you will run into the same problem as doing that. A heavy bullet or case and light powder can weigh exactly the same as heavy powder, and light case or bullet. The conclusion I came to was that if you weighed a box of .22 LR and you found very low standard deviation, that was a sign that the ammunition may be good quality. One box of 50 Lapua Midas M all weighted the same +/- 0.0005 grains. They also shot well. And they should at $14 or so a box of 50.

On the other hand if you take a bulk box of cheapies, and sort them by weight, they do not turn into Lapua Midas M's. I found in very few cases that the accuracy actually improved, and when it did, the difference was not that much.

 

[buzzard]

Sounds very interesting will keep an eye out for your report you may have something.

 

[jr600yd]

Geeeeeezzzzeeeeeeessssssss.......

Sounds like a lot of work for very little in return. Spend more time shooting, reading the wind and having fun.

Good shooting, Jim

 

[Rust]

I'd say that there are a bunch of more important things to consider and work on before you get into a time waster like weighing primers.