Do you trust the book or website for recommended starting loads?

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fchan

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I'm reloading 308 using IMR4895
Webpage states recommended load range is 41 - 45.4gr
Lyman 49th edition states 38-42.5gr

Who do I trust?

*edit for clairty: I was using the Hodgdon/IMR site and comparing the 168grain HPBT loads between the 2 sources.
 
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you need start somewhere, load development is based on pressure signs of the fired case used in your guns.. you can used the recommended starting load of any book, should be ok.. i use Hodgdon Reloading Data Center - data.hodgdon.com .. work up a load beginning with maybe 5 rounds each of 1gr increments.. watch for pressure signs. hope this works for you ,, Merry Christmas
 
Find a third source, and then a fourth. Try to see a pattern. If all but one are really close, drop the outlier. If they are all over the place I usually go with the lowest as a starting value just in case.
I've had to go above listed max loads before in order to find optimum accuracy but I do it slowly and always watching for signs of pressure problems. I've also had to drop below starting loads once to find the most accurate load but again go slow and watch for bad signs. With low pressure you are mostly looking for excessive carbon on the outside of the brass or unburnt powder left in the case and barrel.
 
fchan said:
I'm reloading 308 using IM4895
Webpage states recommended load range is 41 - 45.4gr
Lyman 49th edition states 38-42.5gr

Who do I trust?
Click to expand...
If you were to start at 41 gr of IMR 4895 you would safe. Different barrels, bullets, cases, seating depths, and primers all make a bit of difference in pressure. Its up to you to find the sweet spot.
 
I am relatively confident taking data from sites like Hodgdon and any of the reloading manuals from the majors makers like Sierra, Speer, Lyman, etc. Such loads are tested and scientifically derived and such players will stand behind their data.

I wouldn't ever use load data from personal blogs, websites or posts - sadly, including CGN. Too many cowboys out there, too many hair-raising stories. And of course, different firearms will react differently to the same loads; a round that is merely 'hot' in one might be dangerous in another.

As for the typical warning signs of excess pressure the books and websites mention - flattened primers, enlarged primer pockets, marks from the bolt face etched into the brass, etc, they are not scientific measurements. They're certainly useful indicators in the sense of, "Holy cr*ap - look at that! I'd better drop the load." On the other hand, trying to steadily increase the load until you see them is dangerous as you can have overpressure loads and catastrophic failure without seeing any of them.

Nobody ever lost a rifle firing less-than-max loads.
 
When starting from scratch reloading a new caliber, I first reference the four manuals that I have on the shelf; you'd be surprised to see the variation in max loads from one manual to another (for example, I find the Hornady manual often low-balls the max load when compared to other manuals). Don't get discouraged by the differences, this first step gives me a general idea of the load I'm going to need to get a specific velocity that I'm after. Secondly, I'll search the net to scan realtime experience/opinions on the load that I have in mind. Although I wouldn't bet my eyesight on data coming from a website, I've often come across valuable information that the manuals won't tell me. For example, in my .308 loads for my M-14 I'm using military Lake City cases and through the M1A site I was able to heed the warning that the thicker brass of milspec cases warrants a load reduction of between 0.5gr and 1.0gr due to the smaller inside capacity and increased pressure (so where a book says 41.0gr of H4895 under a 168gr HPBT, I'll go with 40.0gr in Lake City brass). Thirdly, I test my loads with long strings through a chronograph because, at the end of the day, all rifles are slightly different and the load that one guy uses to get 2,600fps out of his M-14 turns out to be too high for my M-14 and vice versa. So you have to reasearch, search supplementary opinions/experiences, and test, test and test to confirm your final load. Piece of cake.
 
"...Web page states..." Which one? They're not all equal. And the bullet weight matters, not the powder.
"...first reference the four manuals..." Far too complicated. You're not loading by an average.
In any case, the manuals and web sites reflect conditions on the day of the tests only. That's why there are discrepancies. Lyman does the actual testing of their data. As do Hodgdon and the other powder and bullet makers. Manufacturers, like Lee, for example, do no testing and use data from other sources. Mostly Hodgdon, as I recall.
 
sunray said:
"...Web page states..." Which one? They're not all equal. And the bullet weight matters, not the powder.
Click to expand...

holy crap, he actually said something i was going to say!

i use the hodgdon, alliant, and accurate website/online loading info all the time. i mostly use hodgdon because i like their powders and they have a ton of info on their site compared to alliant and accurate powders.
 
sunray said:
"...first reference the four manuals..." Far too complicated. You're not loading by an average.
Click to expand...
Never said I load by an average.

I start with a bullet/weight, then, based on the powder I'm using, I look at 3 different bullet makers' and one powder maker's manual to determine/confirm my starting powder charge. I consult 4 (Hornady, Sierra, Speer, Hodgdon) as they can, at times, be notably different in how much powder they say to use for a given velocity. Yes, conditions varied in their individual testing, but I attribute a lot of the differences from corporate risk tolerances (i.e. lawyer input!) When there's a wide variety (and there often is), I'll check out some sites to look at others' experiences with the specific platform that I'm loading for.

If you're happy with one or two sources, all the power to ya. For me, it's like Reagan said: "Trust, but verify."
 
Thanks everyone for the advice here. I ended up starting with the lower end of the scale and going up half grain increments. I have plenty of loads to test and will keep a watchful eye on the cases for signs of stress etc. Once I start getting an idea of where the rifle likes to be I will start narrowing it down closer to the appropriate load :) Still very new to this and I understand there are tons of variables at play here.

I wasn't aware that there was such a variance between the sources but in the end, it's really just a starting point to help you figure out what the best load for that particular rifle are.

sunray said:
"...Web page states..." Which one? They're not all equal. And the bullet weight matters, not the powder.
"...first reference the four manuals..." Far too complicated. You're not loading by an average.
In any case, the manuals and web sites reflect conditions on the day of the tests only. That's why there are discrepancies. Lyman does the actual testing of their data. As do Hodgdon and the other powder and bullet makers. Manufacturers, like Lee, for example, do no testing and use data from other sources. Mostly Hodgdon, as I recall.
Click to expand...

Sorry, I should have been more clear. The IMR/Hodgdon site is the one I was referencing. I was comparing the 168Grain loads from my Lyman book and 168Grain loads from the Hodgdon website. Both were listed for HPBT and referencing the same powder.
 
I generally reference my Lyman manual. Though since I am loading Nosler as well for 308 Win, the Nosler site actually has a good online resource of load data freely available. Sometimes it is worth going directly to the manuals for the bullets you are purchasing, but it isn't really necessary for the most part. Lyman has a lot of good load data and they generally point out what they found to be their most accurate loadings based on their configuration.
 
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