300 Win Mag Load Development Help

[skipglo]

Ok. We'll hell then I guess I ought to just throw it all away and start over. That just doesn't make sense to me with all the once fired brass being sold all over.

This is not meant to offend.....but from the questions you are asking you need a TON of time spent reloading..watch a few hours of You Tube...like 15-20 hours , Ultimate Reloader is a good source along with dozens of others! The difference in mixing brass is HUGE! THE difference in primers equally huge, just a few tiny grains of powder....HUGE. Take small steps...I've been reloading for 49 years and am still learning Son!
Please don't take offense.....just the facts of life!
P.S. once fired brass with the SAME headstamp is okay...but it will be twice fired before its fire formed to your chamber. Just don't expect 1 moa on your first loads and you won't be disappointed!

 

[spladi]

Just starting out reloading and trying to develop a load for my 300 WM. I have some fire formed brass from this rifle approximately 27 pcs and have picked up some once fire brass. I've got it sized and after measuring it almost every piece of the brass fire in my rifle is under SAAMiI overall brass length of 2.62" they are coming in about 2.615 roughly, so
(1) do all these need to be trimmed back to 2.61" or will they be ok for load development
(2) of the 27 pcs of brass shot in this rife they are not same brand of brass some Winchester and some Speer some of the other once fired brass (not in my rifle) is some Nosler and Barnes will using mixed brass make a huge difference in the load developmen? i will also be using a Chronograph for testing. I'm not looking for a load I can shoot F-class with mainly just as accurate a hunting round as I can get.
I will be using 180gr Nosler AB bullets with H-1000 powder using Nosler Load data
Thanks in advance

Maybe sort your brass as to maker and shoot a few groups with the same powder charge and see how much difference it makes on paper. Ideally what you want is uniformity or as close to uniformity as you can get with your reloading, bullets, powder charge, primer and BRASS......all the same in every loaded round. No need to trim until you figure weather it's worth it or not. Your brass is still growing in length within the chamber. Once it has achieved zero growth then you want to bump the shoulder a couple of thousands and then trim the necks

 

[Bob Wright]

OP. On a 300WM it may take 2-3 firings for the shoulder to stop growing forward. I might suggest FL sizing but not bumping the shoulder back until the brass won't fit or they all stop growing at about the same base to shoulder length. Others here might have a different method to accomplish this.

Same on my 7RM. Until l annealed the whole lot, headspace was varying about .004. It can sure mess with your die adjustment if you don't know it exists.

 

[vancewalker007]

Just starting out reloading and trying to develop a load for my 300 WM. I have some fire formed brass from this rifle approximately 27 pcs and have picked up some once fire brass. I've got it sized and after measuring it almost every piece of the brass fire in my rifle is under SAAMiI overall brass length of 2.62" they are coming in about 2.615 roughly, so
(1) do all these need to be trimmed back to 2.61" or will they be ok for load development
(2) of the 27 pcs of brass shot in this rife they are not same brand of brass some Winchester and some Speer some of the other once fired brass (not in my rifle) is some Nosler and Barnes will using mixed brass make a huge difference in the load developmen? i will also be using a Chronograph for testing. I'm not looking for a load I can shoot F-class with mainly just as accurate a hunting round as I can get.
I will be using 180gr Nosler AB bullets with H-1000 powder using Nosler Load data
Thanks in advance

One of the issues that was note pointed out with varying brass manufactures is a safety issue. If you run up tight against your rifle's pressure limit with a load in say Winchester brass, then try the same load in a thicker brass like Nosler you could be way over pressure. Especially in warm or hot weather. So, to minimize this issue you could pick a lower powder node but this is robbing your rifle's true performance. Now most of the large volume manufactures brass will be very similar in thickness ie. Remington, Federal, Hornady, Winchester. I've found Winchester is usually the thinnest of the this bunch.

You can use your mixed brass, just with the understanding that it is not the best approach from a performance and safety standpoint. I've done it in the distant past, usually with Federal, Rem, and Winchester brass.

Just put getting a batch of new brass from 1 manufacturer on your reloading list of to-dos. It doesn't have to be the most expensive brand either for what you are doing. Then get a way to anneal and your brass will last and perform for a long time.

 

[hilbillyconquest]

Just starting out reloading and trying to develop a load for my 300 WM. I have some fire formed brass from this rifle approximately 27 pcs and have picked up some once fire brass. I've got it sized and after measuring it almost every piece of the brass fire in my rifle is under SAAMiI overall brass length of 2.62" they are coming in about 2.615 roughly, so
(1) do all these need to be trimmed back to 2.61" or will they be ok for load development
(2) of the 27 pcs of brass shot in this rife they are not same brand of brass some Winchester and some Speer some of the other once fired brass (not in my rifle) is some Nosler and Barnes will using mixed brass make a huge difference in the load developmen? i will also be using a Chronograph for testing. I'm not looking for a load I can shoot F-class with mainly just as accurate a hunting round as I can get.
I will be using 180gr Nosler AB bullets with H-1000 powder using Nosler Load data
Thanks in advance

BBean70,
I think I have a bag of 50 new Winchester 300 Win brass.
I will donate to you.
Only cost shipping from KY.
P.M. me your address if interested.

 

[JMW67]

^^^ That right there is what its all about good for you

 

[Tulsa Reiner]

Thanks

"Head stamp" = the stamp on the end telling the cartridge type and manufacturer.

 

[Don Titus]

I understand that using the best possible components will yield best results. I am not looking to shoot out to 1000 yards. I am trying to develop a hunting load that I can use to reach out to about 600 yards (practice) with good accuracy that I feel confident If I have to take a shot at 400 yards or hopefully less on an elk as I will be going on my first elk hunt later this year. My new rifle shoots well with factory ammo but like everything right now its hard to find. I've been wanting to start reloading for a while so I figured I would start now. I can seat powder, bullet seat depth, etc play a big role just wasn't aware brass played that big a role or I would not have bought the once fired and bought new premium brass. Not trying to cut corners just save where I can as getting into this hobby the purchases can be endless and the rabbit holes are deep

Just my 2 cents; I've tried several different makes of brass, powders and bullets for my Tikka T3X 300 WM, and I am sold on Peterson brass, H4831sc, and 174 Hammer Hunters seated to magazine length and I'm getting consistent sub 1/2 m.o.a. and 3200 FPS.

 

[Longtine88]

Love Peterson brass. If they make a caliber in the guns I have that's all I use. Especially the king brass for the 300wm

 

[Chrsm]

BBean70,
I think I have a bag of 50 new Winchester 300 Win brass.
I will donate to you.
Only cost shipping from KY.
P.M. me your address if interested.

WOW

 

[Shawn Carverelli]

if your bullet powder combo doesn't work out. you might try rl22 and the 180gr partition

 

[Shawn Carverelli]

after you load the ammo you're hoing to hunt with, I'd run every round through your gun and make **** sure the bolt closes and locks down.
Much better to know a week before than trying in vain to chamber another second round after a miss or the animal doesn't act like its been hit

 

[Lefty7mmstw]

if your bullet powder combo doesn't work out. you might try rl22 and the 180gr partition

rl22 is flat out magic in the 300win. I've been running it with 165's for over 20 years in my 300win. The old girl also dumps 180's accurately with rl22.
It's too bad availability is sketchy at best for rl powders right now.

 

[Longtine88]

Just starting out reloading and trying to develop a load for my 300 WM. I have some fire formed brass from this rifle approximately 27 pcs and have picked up some once fire brass. I've got it sized and after measuring it almost every piece of the brass fire in my rifle is under SAAMiI overall brass length of 2.62" they are coming in about 2.615 roughly, so
(1) do all these need to be trimmed back to 2.61" or will they be ok for load development
(2) of the 27 pcs of brass shot in this rife they are not same brand of brass some Winchester and some Speer some of the other once fired brass (not in my rifle) is some Nosler and Barnes will using mixed brass make a huge difference in the load developmen? i will also be using a Chronograph for testing. I'm not looking for a load I can shoot F-class with mainly just as accurate a hunting round as I can get.
I will be using 180gr Nosler AB bullets with H-1000 powder using Nosler Load data
Thanks in advance

What's your address and name. I'm sending you a box of ADG new 300 WM brass. I don't use adg in the 300wm and have a few boxes. We're trying to get you off on the right foot so you can be accurate and not lock up your bolt on your rifle!