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**Unclenick** · March 12, 2012, 11:04 AM

Parker5920,

Welcome to the forum.

Your combination is good. One problem with .308 is that there is a wide weight and capacity range among different brass headstamps. I've measured cases from 156 grains (Winchester) to 186 grains (IMI) and that represents enough internal capacity to affect some powder charges by a couple of grains. So we'd need to know your cases and knowing your primers may not hurt, though that's a less predictable quantity. For example, if you look at Hodgdon's site they use a Winchester case (high capacity) and Federal 210M primer with the 175 seated to 2.800" COL, and have a starting load of 41.5 and a maximum compressed load of 45.6 grains. Well, if you got some Lake City brass, instead, that top load would have to come down to 44.0 grains to be at the same peak pressure. If you got a some magnum primers instead, another several % might have to come off the powder charge.

So, fair warning there. Start with your loads low and work up in all cases, but especially in .308. Only .300 Win Mag is even worse in this regard. Because of the case variation in .308, I would actually start at 39.2 grains if I had military brass, and more like 40 grains with commercial brass other than Winchester. Remember that performance is useless without accuracy so when accuracy peaks you are wise to stop trying to get more fps out of it.

The above is one reason universal recipes are difficult to come by. Everyone's gun is a little bit different in dimensions and recoil moments, and especially if the brass and primers you have are different, you want to find what your gun actually likes best and fine tune to that. That ability to match the load to your particular gun is the main value to the act of shooting that handloading has, other than reducing cost.

That said, some recipes do fairly well in a number of guns. I recommend Dan Newberry's load development pages for a systematic approach to tuning your own loads. It also puts you on the path to finding those that are a little more universally applicable, should you have a number of guns you want to use the same rounds in. Please note that if you look at his recipe loads you will find they are all put together in Winchester brass, and may be too warm in other brands.

Nick

March 12, 2012, 11:04 AM	#4
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	Parker5920, Welcome to the forum. Your combination is good. One problem with .308 is that there is a wide weight and capacity range among different brass headstamps. I've measured cases from 156 grains (Winchester) to 186 grains (IMI) and that represents enough internal capacity to affect some powder charges by a couple of grains. So we'd need to know your cases and knowing your primers may not hurt, though that's a less predictable quantity. For example, if you look at Hodgdon's site they use a Winchester case (high capacity) and Federal 210M primer with the 175 seated to 2.800" COL, and have a starting load of 41.5 and a maximum compressed load of 45.6 grains. Well, if you got some Lake City brass, instead, that top load would have to come down to 44.0 grains to be at the same peak pressure. If you got a some magnum primers instead, another several % might have to come off the powder charge. So, fair warning there. Start with your loads low and work up in all cases, but especially in .308. Only .300 Win Mag is even worse in this regard. Because of the case variation in .308, I would actually start at 39.2 grains if I had military brass, and more like 40 grains with commercial brass other than Winchester. Remember that performance is useless without accuracy so when accuracy peaks you are wise to stop trying to get more fps out of it. The above is one reason universal recipes are difficult to come by. Everyone's gun is a little bit different in dimensions and recoil moments, and especially if the brass and primers you have are different, you want to find what your gun actually likes best and fine tune to that. That ability to match the load to your particular gun is the main value to the act of shooting that handloading has, other than reducing cost. That said, some recipes do fairly well in a number of guns. I recommend Dan Newberry's load development pages for a systematic approach to tuning your own loads. It also puts you on the path to finding those that are a little more universally applicable, should you have a number of guns you want to use the same rounds in. Please note that if you look at his recipe loads you will find they are all put together in Winchester brass, and may be too warm in other brands. Nick __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle Last edited by Unclenick; March 12, 2012 at 11:09 AM.