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Posted: 1/24/2011 4:01:20 PM EDT
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I am about to load up my first batch of 178gr amax's, but I'm not sure where to start on powder.
My hornady reloading manual 7th edition says max load for imr 4895 is 40.1gr. However the hodgdon website says max load for imr 4895 is 44.7gr using a 180 gr bullet. I was planning to start at about 40gr and work my way up to 43gr or so to use in a semi auto ar. Where should I start? |
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sounds like youre looking at two different powders. If you aint, then go with the newest manual.
107. 2460 (Accurate) 165. Reloader 25 (Alliant) 50. Solo 1250 (Accurate) 108. H335 (Hodgdon) 166. AR2225 (ADI) 51. 3N37 (Vihtavuori) 109. TAC (Ramshot) 167. Retumbo (Hodgdon) 52. 800X (IMR) 110. H4895 (Hodgdon) 168. H870 (Hodgdon) 53. No. 7 (Accurate) 111. 2495 XMR (Accurate) 169. N170 (Vihtavuori) 54. Longshot (Hodgdon) 112. AR2206H (ADI) 170. 24N41 (Vihtavuori) 55. Solo 1500 (Scot) 113. Reloader 12 (Alliant) 171. 50 BMG (Hodgdon) 56. True Blue (Ramshot) 114. 4895 (IMR) 172. AR2218 (ADI) 57. N350 (Vihtavuori) 115. Brig 4065 (Scot) 173. 20N29 (Vihtavuori) 58. 3N38 (Vihtavuori) 116. N135 (Vihtavuori) |
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I think Hodgdon develops their recipes using 24" non-vented test barrels, with bolt action. Other reloading books have a special section or subscripted liner notes for gas gun .308s in the 20-22" bbl range. You should not run bolt gun max. recipes in gas gun autoloaders like the M1A.
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I just went back and checked hodgdons website, I am looking at the IMR 4895. There is a drop down tab where you choose manufacturer.
One thing I noticed when reading in the hornady manual is I am under the section for the m1a. Could this cause the lower than what I thought powder charges? I loaded rounds tonight starting at 37gr of imr 4895, then moved up to 40gr of imr 4895. From 40-42.5gr, I loaded 10 rounds at each half grain amount to test. |
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Quoted: I am about to load up my first batch of 178gr amax's, but I'm not sure where to start on powder. My hornady reloading manual 7th edition says max load for imr 4895 is 40.1gr. However the hodgdon website says max load for imr 4895 is 44.7gr using a 180 gr bullet. I was planning to start at about 40gr and work my way up to 43gr or so to use in a semi auto ar. Where should I start? Start Here: http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1713419&nt=11&page=1 You'll thank me later.  |
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Quoted:
I just went back and checked hodgdons website, I am looking at the IMR 4895. There is a drop down tab where you choose manufacturer. One thing I noticed when reading in the hornady manual is I am under the section for the m1a. Could this cause the lower than what I thought powder charges? I loaded rounds tonight starting at 37gr of imr 4895, then moved up to 40gr of imr 4895. From 40-42.5gr, I loaded 10 rounds at each half grain amount to test. Yes, gas operated autoloaders, particularly the M1a, will show typically lower powder charge recipes. |
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I am about to load up my first batch of 178gr amax's, but I'm not sure where to start on powder. My hornady reloading manual 7th edition says max load for imr 4895 is 40.1gr. However the hodgdon website says max load for imr 4895 is 44.7gr using a 180 gr bullet. I was planning to start at about 40gr and work my way up to 43gr or so to use in a semi auto ar. Where should I start? Start Here: http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1713419&nt=11&page=1 You'll thank me later.
You are right, Thanks. I was trying to find info on the ladder test as you were posting this it looks like. Looks like I may need to get the bullet puller out and reload some of those rounds that I loaded to perform a nice ladder test. Can you get an accurate judge of overpressure signs by firing one round at that charge? |
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I am about to load up my first batch of 178gr amax's, but I'm not sure where to start on powder. My hornady reloading manual 7th edition says max load for imr 4895 is 40.1gr. However the hodgdon website says max load for imr 4895 is 44.7gr using a 180 gr bullet. I was planning to start at about 40gr and work my way up to 43gr or so to use in a semi auto ar. Where should I start? Start Here: http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1713419&nt=11&page=1 You'll thank me later.
You are right, Thanks. I was trying to find info on the ladder test as you were posting this it looks like. Looks like I may need to get the bullet puller out and reload some of those rounds that I loaded to perform a nice ladder test. Can you get an accurate judge of overpressure signs by firing one round at that charge? No, I would load and fire at least 3, unless of course I was getting some SERIOUS pressure signs. For example: I loaded up 50 rounds of my choice load, and for the first 3 or 4 rounds, I got pressure signs. 200 rounds later, no pressure signs (used the exact same load data and powder, from the same lot #). Range conditions were identical. Only thing I could think of was the brass was maybe a little thicker on a few of those rounds. I use LC LR brass almost exclusively, so my data is always different from most peoples, and generally can't go as high as some folks on SH. As always, I suggest 43.0 grains of Varget or RL15, than work up. Also, 43.1 of RL15, a Fed 210M primer, 175 SMK, and a COL of 2.81 is a VERY close copy of M118LR, it gives a nice starting point. |
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Thanks for the help.
I am thinking I am going to shoot the ladder test, and then shoot some 10 round groups with whatever load shoots best to get started. I'll be able to fine tune later on but for now I just want to get a pretty good load for the 178gr amax. I am planning to stick with the imr 4895 powder for now and hope the load will be good to go around 42 grs or so. SecurityForcesmember Thanks for the m118lr clone, thats what I'm planning to work on next once I am satisfied with the 178's. |
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Quoted: Quoted: Quoted: I am about to load up my first batch of 178gr amax's, but I'm not sure where to start on powder. My hornady reloading manual 7th edition says max load for imr 4895 is 40.1gr. However the hodgdon website says max load for imr 4895 is 44.7gr using a 180 gr bullet. I was planning to start at about 40gr and work my way up to 43gr or so to use in a semi auto ar. Where should I start? Start Here: http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1713419&nt=11&page=1 You'll thank me later. You are right, Thanks. I was trying to find info on the ladder test as you were posting this it looks like. Looks like I may need to get the bullet puller out and reload some of those rounds that I loaded to perform a nice ladder test. Can you get an accurate judge of overpressure signs by firing one round at that charge? If you don't exceed the maximum charge in the book, you shouldnt have any issues. I do, however, look at my brass for abnormal indicators when working up a load. That M-118lr clone is pretty much what I load, except I use Varget. |
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I called IMR today and ask my question just to be safe.
The man who answered said the I should be fine starting at 40grs and working up. He only had data for 180gr bullets so thats what he used as a reference. He was guessing that hornady used hornady brass for there test and they could not hold as much powder as the winchester brass used in IMR's test. He said even though they used a bolt gun for testing, I should be safe to start my load at 40grs in an autoloader. 40gr is the max load in the hornady book, but less than the min load listed on the imr reloading data center. This has me wondering, how do I know when my case's have reached max powder capacity for the length bullet I am using? |
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You haven't told us the most important part of this equation yet. What brass are you using. It makes a hell of a difference in .308. No other round has such widely seperated case weights and capacities as does .308.
40 grains of IMR-4895 in a Lake City case and a 178 grain bullet seated @ 2.800" is likely an overload. In a Winchester case probably not. Winchester and Federal 210M primers are the hottest and produce the highest velocities and pressure. Remington 9 1/2's and CCI's standard large rifle primers are the mildest. Using these primers are likely to reduce pressures by almost 6000 c.u.p. That's almost equal to two full grains of powder in .308. Without knowing these variables nobody can know with any certainty where you are going to land as far as pressures are concerned. |
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I am using 06 WCC nato marked brass. This is once fired brass from the winchester 7.62mm m80 ball load thats on the market.
I have thought about putting these 178's into lake city lr brass, but I don't have enough ready to load yet. I am using the federal 210 primers because I bought a bunch of these a while back when just getting into reloading. |
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Quoted:
I am using 06 WCC nato marked brass. This is once fired brass from the winchester 7.62mm m80 ball load thats on the market. I have thought about putting these 178's into lake city lr brass, but I don't have enough ready to load yet. I am using the federal 210 primers because I bought a bunch of these a while back when just getting into reloading. My load is 178 AMAX LR LR brass 43.5 of Varget Fed 210M, 210, and CCI 200 COL is 2.8360 Bugholes form my Rock creek/winchester M70 build. It's not max, but its VERY close. |
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Quoted:
I am using 06 WCC nato marked brass. This is once fired brass from the winchester 7.62mm m80 ball load thats on the market. I have thought about putting these 178's into lake city lr brass, but I don't have enough ready to load yet. I am using the federal 210 primers because I bought a bunch of these a while back when just getting into reloading. Weigh the empty, resized, trimmed and unprimed cases. I imagine they weigh something close to 178/179 grains. If so, you will not be able to use published data as a guideline. Your cases require approximately 2.0 grains less powder than commercial Winchester brass to achieve the same pressures. Start your load development at 38.5 grains of IMR-4895. Use .5 grain increases watching for pressure signs, record velocity if you have a chronograph, shoot the best you are capable of. Once you discover which load groups the best, refine the powder charge around it. I would be very cautious once you get close to 40.0 grains of IMR-4895 when using that brass and bullet in combination. That will be close to maximum. |
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Quoted: Quoted: Quoted: I am about to load up my first batch of 178gr amax's, but I'm not sure where to start on powder. My hornady reloading manual 7th edition says max load for imr 4895 is 40.1gr. However the hodgdon website says max load for imr 4895 is 44.7gr using a 180 gr bullet. I was planning to start at about 40gr and work my way up to 43gr or so to use in a semi auto ar. Where should I start? Start Here: http://www.snipershide.com/forum/ubbthreads.php?ubb=showflat&Number=1713419&nt=11&page=1 You'll thank me later. You are right, Thanks. I was trying to find info on the ladder test as you were posting this it looks like. Looks like I may need to get the bullet puller out and reload some of those rounds that I loaded to perform a nice ladder test. Can you get an accurate judge of overpressure signs by firing one round at that charge? Also, bear in mind that in load development for bolt guns you are going to be concerned with headspace. Always start 'jammed'. On occasion the rifle will prefer a different bullet/rifling relation. Perhaps it be .015” jammed, or .030” out of the rifling totally or .030” "jump.” But start all load work-ups 'jammed'. Work towards 'jump'. |
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