With the light sensor chrony use a small line bubble level to ensure your setting it up the same way and distance each time. Slightest angle or misalignment will account for variances in Vel. PITA some time to ensure level.
When do you stop increasing powder charge??
- Thread starter Gunneegoogoo
- Start date
With the light sensor chrony use a small line bubble level to ensure your setting it up the same way and distance each time. Slightest angle or misalignment will account for variances in Vel. PITA some time to ensure level.
I collect old reloading manuals. My Hogdon manual from 1986 (25th edition) has much higher max loads than my current manual.
I think the point about "lawyerizing" is a good one.
There's something I noticed when reloading my 9mm.
IMI cases fired once, CCI 550 primers, Hodgdon CFE Pistol powder, Winchester FMJ 124gr bullets.
The data from Hodgdon's site lists loads of 4.9gr min to 5.5gr max for Berry's Hollow Base Round Nose Thick Plated, and it's the only 124gr info they have at this time. So I made some trial loads with 5.1gr and 5.3gr, COAL of 1.145-1.150". What I noticed after shooting them out of my Cx4 carbine is quite a bit of soot on the outside of the casings (very much more with the 5.1gr loads than the 5.3gr loads), to the point that there was even soot in the extractor groove and on the head of some of the cases. There's no indication of over pressure from the primer, no bright ring around the base of the cases and no ejector flow marks. Accuracy was very much so-so, no better than the native IMI ammo at about 3 MOA.
What I'm thinking is that the Hodgdon website data might be VERY conservative on the low side... It doesn't seem right that I'd get so much soot from a load supposedly close to max. Mind you, if I their data for 115gr bullets go up to 5.9gr for max load...
Either the 5.3gr load is too weak, the brass is not expanding properly for some reason (is IMI known for hard cases?), or else my chamber could be a tad oversized perhaps? I don't know, I'm definitely scratching my head about this one. I have some Geco once-fired brass I'll have to try with the same loads, see if it does the same thing.
IMI cases fired once, CCI 550 primers, Hodgdon CFE Pistol powder, Winchester FMJ 124gr bullets.
The data from Hodgdon's site lists loads of 4.9gr min to 5.5gr max for Berry's Hollow Base Round Nose Thick Plated, and it's the only 124gr info they have at this time. So I made some trial loads with 5.1gr and 5.3gr, COAL of 1.145-1.150". What I noticed after shooting them out of my Cx4 carbine is quite a bit of soot on the outside of the casings (very much more with the 5.1gr loads than the 5.3gr loads), to the point that there was even soot in the extractor groove and on the head of some of the cases. There's no indication of over pressure from the primer, no bright ring around the base of the cases and no ejector flow marks. Accuracy was very much so-so, no better than the native IMI ammo at about 3 MOA.
What I'm thinking is that the Hodgdon website data might be VERY conservative on the low side... It doesn't seem right that I'd get so much soot from a load supposedly close to max. Mind you, if I their data for 115gr bullets go up to 5.9gr for max load...
Either the 5.3gr load is too weak, the brass is not expanding properly for some reason (is IMI known for hard cases?), or else my chamber could be a tad oversized perhaps? I don't know, I'm definitely scratching my head about this one. I have some Geco once-fired brass I'll have to try with the same loads, see if it does the same thing.
I'm fairly new at the reloading game too but the companies putting out these manuals sure don't make it easy to learn what's right when there is such vast discrepancies from manual to manual and even from one edition to the next. For my .308 165 gn. with Imr4064 the hornady manual had at least a couple grains lower charge than what Hogdon had on their website. Some times the hornady book doesn't even list all of the useable powders that Hogdon does. Even with the 4064 sometimes
The barrel /chamber dimensions vary from rifle to rifle, and powder varies from lot to lot, and the internal volume varies withe the brand and even the lot of cases. Given that everyone producing a manual uses a different rifle for testing, and different lots of powder and cases, of course the data will vary from manual to manual.
It's not real hard. Ejector marks? Back off 2. Sticky bolt lift? Back off 2. Some cases giving ejector marks and some not? Pressures all over the place. Cases need to do Kegels after a shot or three? Back off a smidge. Beating the book by an amount that can't be explained by a quality or longer barrel use your own judgement but you're probably too hot there as well.
*If you management to teach the brass to do primer pocket Kegels share the method.
*If you management to teach the brass to do primer pocket Kegels share the method.
Great information on this thread. I like developing my loads to run as close to max as I can without seeing pressure signs. I try to utilize the case I have but not push it too far, I figure if you want more velocity out of a cartridge just step up to the next one ie. 308 to 300 win mag. It's always safer to get a larger cartridge than to push your existing load too far.
I've loaded some 30 ish rifle calibers now and this it the one thing that has always been true in my testing.
- Location
- Jameson, SK
I guess this is my question:
"What IS the maximum charge??""
We've called the reloading manuals lawyerized and undercharged, some say ANY ejector marks are the limit, some say flatten the primers, some say get a pressure tester, some say you'd have to be a bona fide retard to blow up a gun, some say you could kill the guy beside you at the bench, some say the custom actions can take it, some say velocity is pressure, but velocity plateaus or drops off at high pressures, some says Palma brass is good cause it lets you amp up the .308, others that it lets you murder your action....
This is witchcraft boys!!! This is as almost as bad as the cleaning article I read this AM on 6mmBR....bronze brush, nylon brush, leave it dirty, make it squeaky clean, abrasive paste, tight jag, loose jag, one patch, 2 patches, bore guide, no bore guide, stainless cleaning rod.....holy Christ!!!! Help me jebus!!!
Do I know how to solve this - not a bloody sniff. I know that's not helpful, sorry.
Anyone wanna talk about barrel break in???? I sure don't.
"What IS the maximum charge??""
We've called the reloading manuals lawyerized and undercharged, some say ANY ejector marks are the limit, some say flatten the primers, some say get a pressure tester, some say you'd have to be a bona fide retard to blow up a gun, some say you could kill the guy beside you at the bench, some say the custom actions can take it, some say velocity is pressure, but velocity plateaus or drops off at high pressures, some says Palma brass is good cause it lets you amp up the .308, others that it lets you murder your action....
This is witchcraft boys!!! This is as almost as bad as the cleaning article I read this AM on 6mmBR....bronze brush, nylon brush, leave it dirty, make it squeaky clean, abrasive paste, tight jag, loose jag, one patch, 2 patches, bore guide, no bore guide, stainless cleaning rod.....holy Christ!!!! Help me jebus!!!
Do I know how to solve this - not a bloody sniff. I know that's not helpful, sorry.
Anyone wanna talk about barrel break in???? I sure don't.
- Location
- Jameson, SK
I like shooting, lots.
That's gotta be the long and short of it. I think that all a guy can do is try straddle the fence on safety between the ultra conservative and pushing the limit. Time builds experience and with a little help from above we'll make it to the grave with both eyes and all our fingers.
leveractionjunkie
CGN frequent flyer
- Location
- Kamloops, BC
Ha ha ha ^^awesome^^ and very true. Mankind has never been closer to pure witchcraft than the invention and further development of the rifle. Very little is absolutely set in stone. I guess technically max load is just a hair under the one that locks the gun up or blows it apart. Obviously that'll be higher for your match gun than any of my .308's. I never realized F class guys were so horny on velocity. I've reached the point were if half dozen manuals say my cartridge/bullet/powder combo will get x fps the. I load close to that were I get accuracy without trying to get right on the # or go over it. Then I check that load in a variety of temps if it holds true as far as accuracy and velocity go. Then I use said load and shoot chit with it till I can no longer get component combination any more. If I get way better accuracy 75-100fps below max I don't care I hold a bit higher or turn a bit more elevation. Of course I'm not in the same game as LR competitors so ymmv. Like 6MT said "Shoot lot. Reload lots. Learn lots." so long as chit ain't blowin up its all good
Mystic Precision
CGN Ultra frequent flyer
- Location
- Summerland, BC
As I said previously, the safe limit is magnum pressures... anything more, and you are risking something eventually.
Without pressure trace gear, you are simply going by experience wrt to brass signs, velocity and extraction.
Voodoo... you bet but no one wants to invest in the expensive testing gear and no powder/bullet or reloading company is allowed to produce load data that doesn't agree with SAAMI.
So work up slowly, look for pressure signs, keep an eye on velocity and above all else, what shoots the tightest groups.
As I have said numerous times, you got to get out there and burn some powder and learn it as you go. There are so many variables, there will never be ONE answer BUT you can certainly work up safe ammo based on prudent parameters.
Go shoot, it will become real obvious real fast.
Jerry
- Location
- Jameson, SK
I know, and I'm going to/am.
Is the pressure prediction software to be trusted?? I now clearly understand what is a magnum pressure, but how do I get a pressure reading with all the variables at play in my particular system??
I think at the end of the day it boils down to Art vs. Science, with safety as a guiding principle. Is that a fair statement??
Is the pressure prediction software to be trusted?? I now clearly understand what is a magnum pressure, but how do I get a pressure reading with all the variables at play in my particular system??
I think at the end of the day it boils down to Art vs. Science, with safety as a guiding principle. Is that a fair statement??
- Location
- Jameson, SK
Art vs Science, I think you're right. Black art, specifically. As in: "your max load was vetted by Belzebub".
It's sure a lot of fun as long as nothing blows (that isn't supposed to, I mean).
Ya, you're about right.
I'm 99% confident about not blowing anything up (given the dude on snipershide that was shooting 48 freakin grains of Varget), but shortening my brass life by 80%, or my barrel life.....that's a real concern....
- Location
- Jameson, SK
I have exactly 70. I thought about that too - how much of this is break in????
