Thread: Loading IMR 4895 in 308

Cheers that showing quite different information what I’ve been looking at.

Originally Posted by mattstr

Cheers that showing quite different information what I’ve been looking at.Attachment 206575

Greetings again,
Where did this data come from? Curiosity and a damp morning had me looking through my various data sets. As a WAG perhaps it is Hornady?
GPM.

Originally Posted by mattstr

Cheers that showing quite different information what I’ve been looking at.Attachment 206575

Hodgdon data uses Winchester brass. In my experience has a larger internal capacity than most other brass meaning you'll need a higher charge weight to get the same pressure/velocity than brass with a smaller internal capacity. Hornady data uses Hornady brass which in my experience has on average a smaller internal capacity than Winchester, that's why the charge weights are higher on the Hodgdon data. Internal ballistics is a whole other topic do we should leave it there

Try and use at least the same brand of brass in your load development and final load, it'll save you many headaches.

Same advice as always, start low at the minimum charge weight and work up through the charge weights paying attention to pressure signs and you'll be fine.

Originally Posted by Rated M for Magnum

Hodgdon data uses Winchester brass. In my experience has a larger internal capacity than most other brass meaning you'll need a higher charge weight to get the same pressure/velocity than brass with a smaller internal capacity. Hornady data uses Hornady brass which in my experience has on average a smaller internal capacity than Winchester, that's why the charge weights are higher on the Hodgdon data. Internal ballistics is a whole other topic do we should leave it there

Try and use at least the same brand of brass in your load development and final load, it'll save you many headaches.

Same advice as always, start low at the minimum charge weight and work up through the charge weights paying attention to pressure signs and you'll be fine.

I'm interested in this one brass approach as it is commonly stated. Genuine question here - How much does it really matter for hunting, especially for meat for the table?

Why I ask:
1. Anecdotally, most hunters by far are taking their shots, and kills under 200m with many, possibly the vast majority, under 100m
2. If you are killing for meat, high velocity disintegrating style projectiles are not your friend for body shots. Slower
2000-2600fps, or even down into the mid teens with cast, are going to kill effectively and give a cleaner carcass. So case capacity is hardly an issue if not chasing max velocity
3. Under 200m a 50-80fps velocity variation at the muzzle from different combustion pressures arising from different case capacity is not going to give a meaningful difference in POI, all else being equal.

So I understand the potential importance to bench rest shooters and long distance hunters, or to those wanting reliable head or neck shots where an inch variation might really matter, but for the vast majority of us, should we care?

I do sort and keep my rifle brass in bagged batches of the same headstamp. But I load them all the same if I have an established hunting load. There is more variation in my shooting ability than I will ever get from brass variation I think. The only exception I have personally found is loading 22 Hornet to max loads with frangible tipped Hornady projectiles. Some case brands simply won't seat the bullet over a full charge and allow the round to load in the mag. But that is a different issue I think.

Originally Posted by Jhon

I'm interested in this one brass approach as it is commonly stated. Genuine question here - How much does it really matter for hunting, especially for meat for the table?

Why I ask:
1. Anecdotally, most hunters by far are taking their shots, and kills under 200m with many, possibly the vast majority, under 100m
2. If you are killing for meat, high velocity disintegrating style projectiles are not your friend for body shots. Slower
2000-2600fps, or even down into the mid teens with cast, are going to kill effectively and give a cleaner carcass. So case capacity is hardly an issue if not chasing max velocity
3. Under 200m a 50-80fps velocity variation at the muzzle from different combustion pressures arising from different case capacity is not going to give a meaningful difference in POI, all else being equal.

So I understand the potential importance to bench rest shooters and long distance hunters, or to those wanting reliable head or neck shots where an inch variation might really matter, but for the vast majority of us, should we care?

I do sort and keep my rifle brass in bagged batches of the same headstamp. But I load them all the same if I have an established hunting load. There is more variation in my shooting ability than I will ever get from brass variation I think. The only exception I have personally found is loading 22 Hornet to max loads with frangible tipped Hornady projectiles. Some case brands simply won't seat the bullet over a full charge and allow the round to load in the mag. But that is a different issue I think.

Greetings All,
I was sorting out some loads for a friends .222 earlier in the year, The old loads were with mixed cases srtung vertically about 100mm at 60 metres where the new loads in single headstamp cases produced small groups Ke Waters had chronographed the same load in different cases, again for the .222, varying by as much as 200 fps so this was likely the problem. That said some cartridges seem to plonk most projectiles with different velocities in much the same hole. My experience is that the .308 is not one of those. Regarding the Hornady cases the batch I have are close to identical to later production Winchester. I did read that the earlier Hornady cases may have been made by another firm so current cases could vary from the earlier ones. From my own experience 2 additional grains of powder raised the PoI by around 50mm at 100 metres. It has been stated that US Army brass in the .308 is around 20 grains heavier than Winchester etc and got the same velocity with 2 grains less powder. I have done some loads to check this and will report once they are shot and chronographed. From all this it seems that a significantly heavier case has the copacity to raise the point of impact by as much as 50mm at 100 metres and a little over twice that at 200 metres in the .308. I think that is significant.
Regards Grandpamac.

Originally Posted by Jhon

I'm interested in this one brass approach as it is commonly stated. Genuine question here - How much does it really matter for hunting, especially for meat for the table?

Why I ask:
1. Anecdotally, most hunters by far are taking their shots, and kills under 200m with many, possibly the vast majority, under 100m
2. If you are killing for meat, high velocity disintegrating style projectiles are not your friend for body shots. Slower
2000-2600fps, or even down into the mid teens with cast, are going to kill effectively and give a cleaner carcass. So case capacity is hardly an issue if not chasing max velocity
3. Under 200m a 50-80fps velocity variation at the muzzle from different combustion pressures arising from different case capacity is not going to give a meaningful difference in POI, all else being equal.

So I understand the potential importance to bench rest shooters and long distance hunters, or to those wanting reliable head or neck shots where an inch variation might really matter, but for the vast majority of us, should we care?

I do sort and keep my rifle brass in bagged batches of the same headstamp. But I load them all the same if I have an established hunting load. There is more variation in my shooting ability than I will ever get from brass variation I think. The only exception I have personally found is loading 22 Hornet to max loads with frangible tipped Hornady projectiles. Some case brands simply won't seat the bullet over a full charge and allow the round to load in the mag. But that is a different issue I think.

@john.... many many years ago on a bench shown in recent photo by another member I conducted an experiment with my unsuppressed hard kicking .270 winchester.... there were 3 of us there that day @waimo myself and another fella from timaru..all had .270win rifles... between us we had 10 different types of ammunition... off top of my head...handloaded 110grn speer hp...130grn silvertip factory,130grn hornady reload,130grn Norma factory 140grn reload,couple of different 150s and a belmont supplied lapua 160grn mega...I fired one of each at hundred yards into target as best I COULD and the resulting group was easily covered by an old school playing card...less than 2" wide and 3" high.... so for the next 20 years I just used whatever I had on hand for bush stalking a KNEW it would connect at sub hundy yards for chest/shoulder shooting.
strangely enough my .223 and the .308 I owned would do same thing...only better.
the old SMLE was notorious for different ammunition shooting to different points of impact.
the .308 was great...150s zeroed 2" high and the 180s were bang on at hundy.

I agree, most people don't shoot animals far enough away to notice the difference but it can cause headaches, confusion and be potentially dangerous when developing a load which is relevant here. Using the same brass eliminates a variable, nobody needs to be chasing their tail when doing load development.

Final update. Have tweaked my load slightly and played around with seating depth. Shot my final group today and very happy with my results. Now to load up a few get my point of impact in the correct spot and go find something brown and tasty
Thanks for all your comments