How concerned with weight variation are you?

[Wincheringen]

Most of my rifle reloading involves brass that doesn't weigh much different than the test brass in manuals. I am careful with military 308 brass which is heavier than commercial brass. I segregate that stuff.

My 300 Win Mag project is a little more tricky though. My Nosler 8 manual has all Nosler brass as the test. I have a few pieces that are once fired and they weigh about 220 grains with a fired primer. I've started working with some pulldown Federal brass that weighs 253 grains with a live primer. I used the start load for Ramshot Hunter and 190 grain bullets. It has mild recoil and is very accurate although I didn't run it over the chronograph so I'm not sure of velocity. What do you guys think?

 

[RiverRider]

I think that if you want to match up brass by weight and compare different headstamps by weight, you need to weigh it without the primer.

 

[Wincheringen]

I'm not worried about the 1-2 grain variations, I'm concerned about the 30+ grain variation from test data.

A friend is loading 7MM Weatherby and he has RP brass and Wby brass. The RP brass is 25 grains heavier. Start loads are pushing the limit in his gun.

 

[Tjay]

I think you should run it over the chrono and go from there. My guess would be your top loads would be reached with less powder in the heavy brass. I also would keep the brass separated by weight.

 

[jimbires]

I would sort by water capacity of unsized fired brass . I'd bet different makers brass could weigh different , but have close to the same capacity and vice versa .

 

[Dr. Vette]

What do you guys think?

I think it's one more reason I never mix brands of brass.

I frequently see various Weatherby cases in the same caliber weight the same. However, the capacity and weight of Wby vs RM or Federal, for example, differs. So, I save the other brass for a different load (bullet), or I sell it off. Same is true of various brands of brass for my 270 Win rifles.

Life's too short to try and adjust back-and-forth between brands of brass. Stick with one brand for one load.

 

[Elkman]

From my perspective it really depends on what one is expecting from the rifle and its intended use. First off I don't own a chronograph , and after over 60 years of shooting , doubt that I will. So that removes a variable for me to fuss over. My .300 seems to shoot RP and WW equally well but it is slightly more fussy about bullets. It shoots Sierra BT bullets 1 inch the the right of Partitions. It shoots both under 1/2 MOA. I separate all my cases for my hunting rifles by weight and weigh them empty and ready to load, and never mix them. But as my 45/70 is not a long range hunting rifle, and not one of my primaries I feed it with what ever is handy. I load by head stamp but not by case weight. My 308 is fussy about case brand, it shoot WW in 1/4 MOA, and Lupua in 3/4 MOA. There are lots of variables, but as I said at the start, intended use, kind of drives the need for accuracy.
More ramblings from an old man!

 

[Wincheringen]

Maybe I wasn't quite specific enough. How would you approach data developed for a significantly lighter case like in my example? Is it something people notice? I know some manuals don't give the test brass, and one of the nice features of Nosler 7/8 is that they do give H2O capacity (although I'm not sure how to use their numbers)

 

[OU812]

Maybe I wasn't quite specific enough. How would you approach data developed for a significantly lighter case like in my example? Is it something people notice? I know some manuals don't give the test brass, and one of the nice features of Nosler 7/8 is that they do give H2O capacity (although I'm not sure how to use their numbers)

I would start at a lower charge and work up again. If nothing else load 1 round at each charge weight up to your old charge weight of the lighter brass and check for signs of pressure along the way. Safest way to know.

 

[Wincheringen]

I had to tap the bolt open with a start load of RL17 today so I gotta figure something else out.

 

[jimbires]

take a couple pieces of fired brass . do not resize . weigh the brass case . fill the brass case to the top with water . use a paper towel to absorb the top of the bubble off the water , so the water looks flat with the case neck . weigh this water filled case . subtract these two weights , this is your water capacity . I'd check a few to get an average capacity .

 

[RiverRider]

You might benefit with the help of someone running QuickLOAD for you. The technique I would use is to see what QL says about pressure in a load you know works well in the more voluminous brass (where you supply the water capacity by weight) and matching the pressure to the less voluminous case (whose water capacity you also supply) to see what charge would match up.

 

[Wincheringen]

I haven't done any testing with the Nosler brass, it was picked up at the range. Its a good thing too, I'd really be scratching my head right now if I hadn't found out how much more this weighs than the data brass.

So my FC test piece weighed 254.7 grains empty and 347.2 grains full, for 92.5 grains H2O. The Nosler piece weighed 222.2 grains empty and 317.8 grains full for 95.6 grains H2O. 3.1 more grains of H2O fit in the Nosler piece. 3.35% more capacity.

If somebody wants to run some QL numbers my primer is a Fed 215, loaded to 3.34 OAL, Nosler 190 grain Custom Comp, Ramshot Hunter powder. Thanks!

 

[Wincheringen]

So I'm now reviewing my Western Powders reloading guide and they used Win brass. Their loads are even higher than Nosler. I'm curious as to the various case weights out there.