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> IMR 4064 for the 7x57
IMR 4064 for the 7x57
@ 07:12 pm (GMT) |
John SmithI am working on an elk hunting load for my Ruger No. 1A in 7x57. I have been reloading with IMR 4064 powder behind the 162 gr. Hornady A-Max.Accuracy at the range has been good with these components. But I have a problem with how much powder to safely use. The Nosler reloading manual list a maximum load of 39 grains of 4064. My older Hornady reloading manual lists a maximum load of 42.4 of 4064. Why such a difference? And which would Nathan choose? Or would he choose a different powder? |
Replies
@ 07:59 pm (GMT) |
charlie porterRe: IMR 4064 for the 7x57hi john 7/6/13I noticed your question regarding 4064 powder. the following info is on the house! actually the recommended powder for your 162 gr bullet is imr 4320 which is a bit slower but certainly 4064 would burn fine and produce tight groups. id recommend starting at 40.0 grains as is the starting charge for 4320 which is a very similar powder- almost interchangeable with 4064 but a finer grained powder for easier metering. but to best answer your question I would need to know: 1) the length of your 162 gr bullet 2) your case capacity( which on average is 54.5 gr) 3) the overall cartridge length you plan to use with your 162 gr bullet. then I could calculate your recommended starting charge of 4320 or at least give you a fairly accurate starting charge of 4064. at this point I can tell you that 40.0 gr of 4320 is approximately 48000cup pressure. you may be wondering who I am so ill tell you that I have a part time business calculating and recommending specific starting powder charges of specific powders for specific bullet weights and case capacities of centerfire rifles for those who want to save time and money developing optimal loads for their rifles. again ill be happy to develop your optimal starting charge weight for you on the house! Charlie porter .308win specialist 508-244-8898 [email protected] |
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@ 09:06 pm (GMT) |
John SmithRe: IMR 4064 for the 7x57Thank you for your quick response and the on the house offer. My 7x57 Ruger No. l was made in1979 and has the standard 22 inch barrel. The Hornady 162 A-Max bullet is 1.43 inches. Case capacity is about 47 grains. The OAL I'm using is 3.340 inches. Yea I know the bullet seems to be sticking way out there, but the rounds chamber easily in my Ruger and I want them close but not touching the lands and grooves. I use a RCBS RangeMaster 750 scale. |
@ 09:13 pm (GMT) |
Nathan FosterRe: IMR 4064 for the 7x57Hi John, I have run up to 44gr of 4064 in the past during testing (Norma Brass, Fed 210 primer). However best accuracy is often around the 42.5 to 43 grain mark, depending on individual bore tolerances. The difference in your manuals is based on concerns over older rifles.As always, work up test loads in half grain increments to begin with, watching for pressure signs. I always try to determine where actual max or near max is for each individual rifle as opposed to book max. That way I have a full understanding of the rifle and can look for both low and high pressure sweet spots (accuracy). I tend to use H4350 a lot with heavy bullets in the 7x57, working up to 49 grains (2800fps) with the 162gr A-max in some instances during testing. Occasionally I will strike it lucky and get the extra velocity I am looking for with excellent accuracy, as high as 2770fps (26" barrel). But other times the lines are blurred with tests showing no major differences in velocity / accuracy with either powder- especially in 22" barrels for obvious reasons. |
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@ 09:59 pm (GMT) |
Nathan FosterRe: IMR 4064 for the 7x57Hi John, your COAL is too long for optimum bullet to bore alignment (concentricity). Please see the COAL article on this site.You need to reset COAL to 3.094 and then forget about seating depths as a variable (unless you want to go deeper- if initial test loads do not produce desirable accuracy). Neck tension of cases will be important. Make sure the case neck expander button on your FL/Neck die is polished and not expanding the case necks to a loose fit. An outside neck diameter of .304" after sizing would be ideal. |
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@ 10:12 pm (GMT) |
charlie porterRe: IMR 4064 for the 7x57hi again johnthanks for furnishing me the bullet length and coal info. now based on a 162gr 1.43lg bullet and full case capacity of 54.5 grains fitted to a coal of 3.34 in -the most efficient powder is imr 4320 at a starting charge of 40.5 gr for an approximate pressure of 47500 cup and muzzle velocity of 2525 fps. recommended maximum charge wt is 42.0 gr imr 4320 for approx. velocity of 2620fps at 51000cup. if your really set on imr4064 you could start at approx. 40 gr and look for pressure signs along the way. for this case capacity slower burning powders like imr4350 and imr4381 aren't efficient enough and wouldn't burn completely leaving inconsistent pressure issues from shot to shot. your 162 gr .284 dia bullet is a high sectional density bullet requiring a slow powder but your case capacity is medium keeping the powder burn rate at a medium slow burn rate that imr4320 offers. Charlie [email protected] 508-244-8898 |
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@ 11:17 pm (GMT) |
Nathan FosterRe: IMR 4064 for the 7x57Charlie, I have not had pressure issues from shot to shot with 4350 in 22-26" barrels. Just looking in my client rifle journal now, ES was between 10 and 15fps with optimum loads.Primer burn rate will effect results, neck tension will effect results, internal bore finish, rate of fouling, brand of bullet, style of bullet. No doubt you are constantly trying to overcome such variables in your program, narrowing the gap between theory and reality. Your suggested load range looks good, very useful. |
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@ 12:04 am (GMT) |
Nathan FosterRe: IMR 4064 for the 7x57Charlie, your start load with IMR 4320 is quite a bit above book max. Your data reflects the cartridge capacity etc without going into old versus new rifles. Very useful. |
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@ 01:26 am (GMT) |
charlie porterRe: IMR 4064 for the 7x57hi- ive been away for a while but have now noticed a concern over the charge weight of 40 5 gr imr4320. understandable but the rifle is a modern ruger single shot I believe and the 3.34 coal is excessively long in john's case - but what he wants -apparently due to the relationship of a long bullet seating arrangement relative to the land origin he has determined to be ok by fit. in turn the effective case capacity has increased allowing a slightly higher charge of 40.5 gr vs a normal starting charge of approx. 38.5 gr at standard 7 x 57mm coal.charlie |
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@ 01:35 am (GMT) |
John SmithRe: IMR 4064 for the 7x57I will try 40.8 grs of 4064 and an OAL of 3.094 and see ifaccuracy holds up. |
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@ 01:52 am (GMT) |
Nathan FosterRe: IMR 4064 for the 7x57I have no concern Charlie, your math has looked good all along.John, please start with Charlie's suggested 40 grains 4064, then work up, three shot groups, half grain incremental charges to 42.5 grains for starters. Your rifle will probably be capable of using more powder due to the throat length but 42.5 is a good preliminary max for the first session. Don't forget to include a fouling shot. |
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@ 12:59 pm (GMT) |
John SmithRe: IMR 4064 for the 7x57Test fired the 7x57 with 40.8 gr. of 4064 and OAL of 3.094. Lessaccuracy, but maybe it was just me. For my next test fire I will up the 4064 slightly. |
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@ 06:48 pm (GMT) |
Nathan FosterRe: IMR 4064 for the 7x57Hi John, why did you not utilize incremental load development?Please, please work up loads in a simple and concise fashion. 1 fouler @ 40 grains 40gr x 3 40.5 x 3 41 x 3 41.5 x 3 42 x 3 42.5 x 3 43 x 3 Observe cases, observe targets. Decide on whether it is safe to pursue load work to 44 grains. Or, if partial sweet spot found, work around sweet spot in .2 grain increments. Use good forend / forehand technique as outlined in the hold that forend article, good sling tension. No bipods during testing, use sand bags, bipods can be fitted later. Hope the above helps. |
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@ 07:04 pm (GMT) |
John SmithRe: IMR 4064 for the 7x57Hi Nathan,Okey, I have reloaded my 162 A-Max, 7x57 rounds in the increments you suggested. Starting at 41 grains of IMR 4064 and going up to 43 grains. The next day without much wind or heat I will try them out at my club's range. Thank you for your help. |
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@ 10:11 pm (GMT) |
Nathan FosterRe: IMR 4064 for the 7x57Good luck John! |
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@ 02:40 pm (GMT) |
John SmithRe: IMR 4064 for the 7x57On a hot (92 degrees) windless morning I found that I got my best accuracywith a load of 42.5 grains of IMR 4064. Thanks for your help. In October I will be hunting deer in Washington with my 6.5x55 Ruger No. lA, then moose in Vermont with a loaner Win. Model 70 in 30.06, then returning to Washington state to hunt elk with my 7x57 Ruger No.lA. It's going to be a busy October. |
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@ 04:57 pm (GMT) |
Nathan FosterRe: IMR 4064 for the 7x57Good to hear John. OK, keep your camera handy! |
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