I was looking at the alliant reloading book for a load for 243 with a 70 grain bullet and RL15 powder. The book suggest max load of 43.5 grains. I looked at the Sierra loading info and they suggest a 39.9 grain max with a slower velocity. Looking around the web I find loads suggested more in the 41 grains range. I looked in the reliant suggeted loads online and for a 75 grain 243 bullet they had recomended a 43 grain load of RL15. It seems like the 41 grain RL15 would be alright with a 70 grain bullet. Any thoughts?
Max load difference
- Thread starter GLA.OR
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SWNMHUNTER
New member
My guess would be different guns used in their testing. Reloading books are nothing more than a guide as each gun is different so each guns max load will vary.
What SWNMHUNTER says is right on. The Sierra Manual (my usual loading manual) has loads recommended for their bullets as fired in the test weapon listed on the first page of every caliber. Personally I pretty much stick with either the "Accuracy Load" or use the max load )in green) for testing purposes. The only problem with the info on the powder bottle is the weapon they suggest those loads for are not listed. So I guess you have to make a decision which way you want to go. A simple method that I sometimes use is when I get at the "Max Load" recommended, I feel the casing immediately after firing the round. If its REALLY hot to the touch, it time for ME not to go any further. If it is warm but not super hot, I might consider going just a tad more (perhaps .5 gr) but I don't like to push it simply for safety reasons and I don't want to damage to my weapon.
But do some testing and have somefun, being careful as well.
But do some testing and have somefun, being careful as well.
OldTurtle
Moderator - Deceased
For safety reasons,,,Take your powder manufacturer's published max. load, drop down at least a full 1.5 grains of powder from that amount and work up a series of loads in .3gr increments....at least five each...starting with the lowest charge, shoot the five to see what kind of group you are getting and do this with each charge weight. You smallest group will be your best accuracy load...
Inspect the fired cases as you shoot them for signs of excessive pressure... case heads starting to flatten (letters not as deep), primers starting to flatten considerably, or pockets starting to develop around the firing pin indentation...,,or
If you are shooting a bolt action and the bolt starts getting hard to lift... you are getting on the on the 'border line' of pressure problems...
Rule #1... Never use someone else's load data off the internet....each rifle can be a little different and my load may cause a serious problem in your rifle...
Rule #2... Always follow Rule #1
Inspect the fired cases as you shoot them for signs of excessive pressure... case heads starting to flatten (letters not as deep), primers starting to flatten considerably, or pockets starting to develop around the firing pin indentation...,,or
If you are shooting a bolt action and the bolt starts getting hard to lift... you are getting on the on the 'border line' of pressure problems...
Rule #1... Never use someone else's load data off the internet....each rifle can be a little different and my load may cause a serious problem in your rifle...
Rule #2... Always follow Rule #1
What I have done since none of my rifles are the same as they ( Sierra, Hornady, Nosler, ECT.) use I add up all the max loads for the bullet weight and powder I am going to use and take the average as my MAX load. Then start 2 Grins lower than Average Max load and load 5 rds. for every .5 grains till I hit the Average Max load and watch for pressure signs as I go.
DAB
DAB
Last edited:
Don Fischer
New member
Whatever powder/bullet combination I'm loading for the first time, I start several grains below max and in .5 gr increment's work up one round at a time to 1 gr over listed max. Then I fire each one starting at the light load and carefully look for any pressure signs till I find pressure or reach 1 gr over max. That is the only way I know of to find the max load for your rifle!
Whatever rifle they list in the manual makes no difference unless it's a military cartridge tested in a modern arm and your using a military arm. Keep in mind the rifle they used was not your's!
Whatever rifle they list in the manual makes no difference unless it's a military cartridge tested in a modern arm and your using a military arm. Keep in mind the rifle they used was not your's!
SWNMHUNTER
New member
Even though I'm not Don I'll give you some sings of excessive pressures. Flatting of both primers and cartridge base is one. This can be both seen and measured. If you look carefully at the case head you will start seeing the markings looking blury. To measure it just measure the base of fired case and compare to what it should be. If you are getting flatting it wil be bigger. Metal flowing into firing pin hole is another. This is indicated by a small ridge of metal around indention left by firing pin on primer. Pressures are really getting up there when the bolt is hard to open. This is because the pressure is setting the locking lugs on the bolt back itno the reciever. These are just a few of the signs of excessive pressures.
This whole business of determining what is a safe place to start with a given bunch of components is probably one of the most confusing issues a new reloader has to address. The idea is, first and foremost, that you don't want to exceed the maximum safe peak operating pressure for your particular rifle/cartridge combination. Now consider all the things that affect that pressure: different lots of the same powder can vary in burning rate; different bullets of the same weight can effect pressure according to the particular jacket material used, the length of the bearing surface of that particular design, and the jacket thickness. Case capacity affects pressure: all other things being equal a lower capacity case gives greater pressure with the same powder charge than does a case of higher capacity. Different primers can give different pressures. The configuration of your rifle's throat can affect pressure, as can the depth your bullet is seated. The distance your bullet travels before engaging the rifling affects pressure. The amount your rifle bore deviates above or below the nominal size and the rate of rifling twist affect pressure. Here's my system for determining a starting load. Knock on wood, in thirty six years of reloading I've never destroyed a rifle or had a reloading-caused mishap. First, get multiple sources for data. Get at least a couple of bullet manufacturers' manuals. I use Sierra and Nosler. Also get all the powder manufacturer's manuals you can lay your hands on. A reliable internet source is loaddata.com, by Wolfe Publishing. Most of the manufacturers have data available on line as well. If I can find a load listed in a reputable source that uses all the exact same components I'm using, powder, bullet, primer and case, I drop ten percent and start there. If I can't find an exact match I look at all the combinations I can find for that weight bullet and that particular powder. I throw out any that are real high or real low, average the rest and start ten percent below that average. I start with my bullet seated .050 off the lands or at the maximum length that will work through the magazine, whichever is shorter. In other words, if a load that is .050 off the lands is too long to work through the rifle's magazine, I seat it in until the loaded round will work through the magazine. I only load a couple of rounds to start and usually fire them outside my shop to see if I have any signs of excessive pressure. If not, I load three rounds each of five loads, increasing the powder charge in half grain increments. These I take to the range and starting with the lowest powder charge, shoot for accuracy and velocity over my chronograph. When I get to a point where I've hit near the average top velocity for that bullet/powder combination in one or more of my (reliable) data sources, or when I start seeing excessive pressure signs, I quit. If I hit the speed I want and get the accuracy I want, life is good. If not I start trying some tuning, usually involving cartridge overall length. Anymore that doesn't often seem necessary in a good rifle. Now the question is, what are excessive pressure signs? As has been mentioned, hard bolt lift is one. If you've got a bright spot on your case head where the brass extruded back into the ejector hole or slot in the bolt face, then was scrubbed off when the bolt was turned, you are on the brink of disaster. Likewise if your primer is really flattened out, filling the primer pocket to the edges and has the machining marks of the bolt face imprinted in it. If your chronograph is showing significantly higher velocity than the max load listed in your data sources for that weight bullet in that cartridge you are pushing pressures too high as well. It's a good idea to stick with powders that, over the years, the reloading community has determined are a good match with the cartridge and bullet weight you're reloading. Also keep in mind, you can't change the laws of physics. If you're getting a significantly increased velocity over the maximums listed for a particular bullet weight in a particular cartridge, you are running at significantly increased pressure. You can do this in a rifle for a while without things coming apart, but you're stressing the rifle beyond its design parameters and eventually someone has to pay the piper. Pick your way along carefully. Knowledge is your best defense. Learn everything you can as you go along. Learn from reputable sources. Be especially careful of advice you get on internet forums. There are a lot of good people online who can give you a lot of help, but honestly, some of the stuff I see promulgated by some of the self professed internet experts is downright scary. Good luck.
Don Fischer
New member
Originally Posted By: ShynlocoOK Don, I'm interested! I've heard that phrase "pressure signs" before, but have yet to hear or read a detailed explanation of what to SPECIFICALLY look for as a PRESSURE SIGN. So educate me and please list all the characteristics you can think of. Thx!
Things I watch for pressure are: extreame flatting of primer, head expansion over SAMMI spec, leaks around the primer pocket, extractor mark on the rim, hard opening bolt. Some of these by themselves might not be a sign but you get a couple I'd call it a sign and be safe. Flattened primers by themselves are not to me a sign, extreamly flattened are. Often with that extreamy flattened primer you'll also see an ejector mark on the case and a gas leak around the primer. If the bolt opening get's hard, you have by passed signs and are way to far over.
Things I watch for pressure are: extreame flatting of primer, head expansion over SAMMI spec, leaks around the primer pocket, extractor mark on the rim, hard opening bolt. Some of these by themselves might not be a sign but you get a couple I'd call it a sign and be safe. Flattened primers by themselves are not to me a sign, extreamly flattened are. Often with that extreamy flattened primer you'll also see an ejector mark on the case and a gas leak around the primer. If the bolt opening get's hard, you have by passed signs and are way to far over.
First off royboy99 and and Don Fischer, thanks for your responses. You guys and many others on this blog, are the reason I don't bother even getting on any of the other blogs because of the apparent wealth of knowledge and information, coupled with the willingess to take the time to explain some very complicated issue in reloading. So a tip of the hat to all those out there who continue to educate an old fart like me.
As many of you may have already guessed, I'm pretty new to this reloading business even though I've been shootin all sort of weapons since I was a young teenager. Another perhaps apparent issue is that I'm not the sharpest blade in the drawer of reloading simply because analytical issues have often escaped me, plus whenever I fired weapons (up until about 6 months ago), in every case the ammo was either commercial or reloaded by someone else. I never had the time nor inclination to learn as my time seemingly was taken up by working or more of accuracy in shooting and tactical movement issues, both throughout my military service and in law enforcement. Even then, my sniper team partner did the reloading as he had both the time and equipment. But once I retired and located a local range, I became like a kid in a candy store. And actually with alot of your help and some practical exercises from guys I met at the range, I've learned to reload. I find it both very entertaining and sometimes down right frustrating, because I've found, some of the accepted guidelines don't work in every sitation and weapon. But that too keeps me on my toes to recognize when something is amiss and you good folks continue to educate me on the cures and how to avoid them in the first place. So you can bet I've already printed out the information you've supplied and keep it on my reloading bench for reference and a checkoff list (if you will) in knowing what to look for as far as too much pressure and some of the associated factors causing that condition. Now don't be surprised if I ask some really anal questions later on because as I come across issues I don't truly understand, don't be surprised to be getting a PM for further explanation.
But as always, thanks to a great bunch of folks on this blog.
As many of you may have already guessed, I'm pretty new to this reloading business even though I've been shootin all sort of weapons since I was a young teenager. Another perhaps apparent issue is that I'm not the sharpest blade in the drawer of reloading simply because analytical issues have often escaped me, plus whenever I fired weapons (up until about 6 months ago), in every case the ammo was either commercial or reloaded by someone else. I never had the time nor inclination to learn as my time seemingly was taken up by working or more of accuracy in shooting and tactical movement issues, both throughout my military service and in law enforcement. Even then, my sniper team partner did the reloading as he had both the time and equipment. But once I retired and located a local range, I became like a kid in a candy store. And actually with alot of your help and some practical exercises from guys I met at the range, I've learned to reload. I find it both very entertaining and sometimes down right frustrating, because I've found, some of the accepted guidelines don't work in every sitation and weapon. But that too keeps me on my toes to recognize when something is amiss and you good folks continue to educate me on the cures and how to avoid them in the first place. So you can bet I've already printed out the information you've supplied and keep it on my reloading bench for reference and a checkoff list (if you will) in knowing what to look for as far as too much pressure and some of the associated factors causing that condition. Now don't be surprised if I ask some really anal questions later on because as I come across issues I don't truly understand, don't be surprised to be getting a PM for further explanation.
But as always, thanks to a great bunch of folks on this blog.
Shynloco - I'm a long way from what I'd consider an expert, but I've been doing this a long time. My memory might not be the best, but I remember what it was like starting out, all the questions I had, and how much of the seemingly contradictory information I had to pick through. I manage to keep myself out of trouble and get pretty good results loading almost all my centerfire rifle and handgun ammo and a lot of my shotgun ammo. Always glad to help another shooter. Also, I'm not afraid to say "I don't know." I'll never make something up or take a shot in the dark. If I don't know, I keep my mouth shut. One piece of advice, if you haven't already, get yourself a chronograph. Without one you are truly just flying by the seat of your pants. These days you can get one for a hundred bucks or so, may not be lab grade, but sure a benefit to the reloader. Have at it.
Great thread guys. I picked up some good info.
Something kinda surprising to me is I did the step up method but only used the Sierra manual. Shot in two rifles, a customized Rem 700 and a cooper 21. Set each group .02 off the lands. All the loads shot much faster (200 fps+)than the advertised data but only those shot in the cooper started showing pressure signs. Did not even try the last two groups in either gun.
Curious stuff. Thank heavens for the chronograph.
The Sierra manual seems to let you push their bullets faster.
A new guy on his own could get into trouble without a resource like this site.
Something kinda surprising to me is I did the step up method but only used the Sierra manual. Shot in two rifles, a customized Rem 700 and a cooper 21. Set each group .02 off the lands. All the loads shot much faster (200 fps+)than the advertised data but only those shot in the cooper started showing pressure signs. Did not even try the last two groups in either gun.
Curious stuff. Thank heavens for the chronograph.
The Sierra manual seems to let you push their bullets faster.
A new guy on his own could get into trouble without a resource like this site.
Originally Posted By: SWNMHUNTERMy guess would be different guns used in their testing. Reloading books are nothing more than a guide as each gun is different so each guns max load will vary.
+1
Have you ever thought how guys work up loads for wild cat cartridges where there are no reloading reference manuals? I start at the max load for the parent cartrige, load one shot and one shot only increasing my powder charge by .5g at a time till I see pressure signs. I mark the load with the pressure signs and never go to that point again. We have shot a lot of military surplus powder where there is no loading info for at all, especially if loaded in a wild cat cartridge.
Reloading manuals are hit and miss, especially the old ones. Some barrels will not let you get anywhere near a published max loads, while others will allow much more. Different lot# of powder have a huge diffenence in a Max load for your rifle in my experience.
+1
Have you ever thought how guys work up loads for wild cat cartridges where there are no reloading reference manuals? I start at the max load for the parent cartrige, load one shot and one shot only increasing my powder charge by .5g at a time till I see pressure signs. I mark the load with the pressure signs and never go to that point again. We have shot a lot of military surplus powder where there is no loading info for at all, especially if loaded in a wild cat cartridge.
Reloading manuals are hit and miss, especially the old ones. Some barrels will not let you get anywhere near a published max loads, while others will allow much more. Different lot# of powder have a huge diffenence in a Max load for your rifle in my experience.
Originally Posted By: SWNMHUNTERMy guess would be different guns used in their testing. Reloading books are nothing more than a guide as each gun is different so each guns max load will vary.
+2
I use one load in particular that the starting load in one manual is higher than the max load in another, using the same components. Always start low and work up.
+2
I use one load in particular that the starting load in one manual is higher than the max load in another, using the same components. Always start low and work up.