Getting Maximum Performance From Reloads
This post was originally in response to the "Hornady Light Magnum Question," but I would like to get other opinions, if they've had similar or different experience. Thanks.
"I don't know what factory process is used for the Hornady Light Magnum ammunition, but you can equal or exceed their velocities without excessive pressures, if you're willing to tap in powder and use compressed loads.
I have a .257 Ackley Improved (AI), .25-06 AI, .280 AI, and 30-06 AI. All guns are custom made bolt-action rifles (Rem M700 or Win M70) with match-grade 26" barrels. I have developed loads for all by experimenting with almost all available modern powders and by chronographing every test firing. I've developed these loads in conjunction with the NECCO Internal Ballistic Program. I have reams of data.
The best performance - at a given pressure for a given weight bullet - is almost always obtained with the slowest burning powder that will fill the case and bring the maximum pressure to the desired level. For example, consider Reloader 25 in a 30-06 using 165 or 180 grain bullets with no higher than 65,000 psi. A standard Winchester 30-06 case will roughly hold 66 grains of R25, when tapped in and the powder compressed by the bullet. Reloader 25 compresses nicely, and with tight case necks the bullet will not be pushed back out by the compressed powder. With a 24 inch barrel, maximum velocity with a 180 bullet will be right at 3000 fps, and with a 165 grain bullet right at 3100 fps.
I would NEVER recommend starting with this load, but rather recommend working up to it by starting from 62 grains of R25 - then incrementally increasing the charge by 0.5 grain increments until serious pressure signs develop or you achieve 66 grains.
I'm willing to tolerate "significant" pressure - that is, pressures often used when loading the .270 or some of the new magnums. (These new magnums look good, because they're being loaded to pressures significantly higher than the older calibers - well over 60,000 psi - even close to 64,000 psi. Hence, the comparisons to the "old" are not fair; remember, the companies want to sell new guns.)
A standard modern bolt-action rifle will tolerate about 160,000 psi; hence, you're not in danger of bursting the gun - not even close. But, you don't want to load beyond 65-70,000 psi, because beyond that pressure you can get a sticky bolt or even a frozen case in the chamber - a disaster, if you need a second shot at the trophy of a lifetime. Loading to 65,000 psi will loosen those primer pockets fairly quickly. To test for loose primer pockets, I hand prime all cases and "feel" the primer into the pocket - indeed, you can consider your brass case you type of "copper crusher" pressure gauge. I don't care too about multiple reloadings of a single case, because cases are cheap, expendable, and very easy to replace.
Finally, I've found that Reloader 25 is single best slow-burning powder on the market. I routinely get the best performance - both accuracy and velocity - with the lowest pressures. Yet, you must load a relatively heavy bullet. When you go to lighter bullets (e.g., 150 or 130 grain for the 30-06), you'll need to use R22 or R19 to achieve maximum desired pressure.
Regards, Ackley Improved User"
"I don't know what factory process is used for the Hornady Light Magnum ammunition, but you can equal or exceed their velocities without excessive pressures, if you're willing to tap in powder and use compressed loads.
I have a .257 Ackley Improved (AI), .25-06 AI, .280 AI, and 30-06 AI. All guns are custom made bolt-action rifles (Rem M700 or Win M70) with match-grade 26" barrels. I have developed loads for all by experimenting with almost all available modern powders and by chronographing every test firing. I've developed these loads in conjunction with the NECCO Internal Ballistic Program. I have reams of data.
The best performance - at a given pressure for a given weight bullet - is almost always obtained with the slowest burning powder that will fill the case and bring the maximum pressure to the desired level. For example, consider Reloader 25 in a 30-06 using 165 or 180 grain bullets with no higher than 65,000 psi. A standard Winchester 30-06 case will roughly hold 66 grains of R25, when tapped in and the powder compressed by the bullet. Reloader 25 compresses nicely, and with tight case necks the bullet will not be pushed back out by the compressed powder. With a 24 inch barrel, maximum velocity with a 180 bullet will be right at 3000 fps, and with a 165 grain bullet right at 3100 fps.
I would NEVER recommend starting with this load, but rather recommend working up to it by starting from 62 grains of R25 - then incrementally increasing the charge by 0.5 grain increments until serious pressure signs develop or you achieve 66 grains.
I'm willing to tolerate "significant" pressure - that is, pressures often used when loading the .270 or some of the new magnums. (These new magnums look good, because they're being loaded to pressures significantly higher than the older calibers - well over 60,000 psi - even close to 64,000 psi. Hence, the comparisons to the "old" are not fair; remember, the companies want to sell new guns.)
A standard modern bolt-action rifle will tolerate about 160,000 psi; hence, you're not in danger of bursting the gun - not even close. But, you don't want to load beyond 65-70,000 psi, because beyond that pressure you can get a sticky bolt or even a frozen case in the chamber - a disaster, if you need a second shot at the trophy of a lifetime. Loading to 65,000 psi will loosen those primer pockets fairly quickly. To test for loose primer pockets, I hand prime all cases and "feel" the primer into the pocket - indeed, you can consider your brass case you type of "copper crusher" pressure gauge. I don't care too about multiple reloadings of a single case, because cases are cheap, expendable, and very easy to replace.
Finally, I've found that Reloader 25 is single best slow-burning powder on the market. I routinely get the best performance - both accuracy and velocity - with the lowest pressures. Yet, you must load a relatively heavy bullet. When you go to lighter bullets (e.g., 150 or 130 grain for the 30-06), you'll need to use R22 or R19 to achieve maximum desired pressure.
Regards, Ackley Improved User"
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Thanks for the info AIU, sounds like you've spent some time on it. I started the "Hornady Light mag" thread simply out of curiosity, I'm quite happy with the way my 30/06 shoots (accurate), and the performance ( kills big animals dead ), so I have no complaints or wants in that dept. I was wondering just how they did it. I too have experimented with over maximum and compressed loads, not to the extent you have, but have found for my uses they would not work. I don't want or need to push the envelope for my hunting rifles simply because I want to keep it simple and don't want a sticky bolt or a case head seperation or worse if I need a follow up shot on an animal of a lifetime, I hunt in remote and rugged country and have never yet had to stop a hunt to hike out to fix my equipment, I hope it never happens so for me I choose to remain a little "under loaded" for my uses. Please no slight intended hopefully none taken on your part, you obviously have a lot of experience and time invested in your loads. 0 -
Snellstrom, have you ever tried Reloader 25? It's such a slow burning powder, it's very hard to get into pressure problems. 0 -
No I haven't but after hearing your suggestion I think I will, thanks.
My brother swears by the "RL" powders in his .257 Roberts and .243 and keeps telling me to give it a try in my Roberts and .243. The gun I hunt most with is my 30/06. My gun is real finicky but years ago I found that it shoots 180 grain boat tail bullets of almost any brand with 56 grains of IMR 4350 to just under 1" at 100 yards, for a lightweight bolt action this is fine for me. If I change anything in the above load my groups get big real fast( bullet weight, shape, different powders) So I have always been reluctant to change what is working almost perfect. I'm sure I'll give the RL a try though. My pet project this summer though is to just shoot my 375 H&H a lot for my upcoming Moose hunt in Alaska. Practice practice.....0 -
Snellstrom, thanks for the replies. I've found R19 to work best with 165 gr. bullets and R25 to work best with 180 gr. bullets. The 30-06 AI and standard 30-06 are more alike than different - the AI holds 3-4 grains more and gets ~100 fps more than the standand 30-06. These differences don't matter much in the field. Good luck getting that big one. Regards, AI User 0
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