Spike Camp

Another example of why it is still important to cross reference reloading data

Most reloaders use several resources; manuals / websites / Quickload etc. A recent experience reminded me again of how important this is.

The Lyman Pistol and Revolver Handbook is a great resource for loading data, which also mostly includes pressure numbers for the loads. I've had mine a while and now that we have imported propellants available and our local producer is closed / not producing, following a very unfortunate incident at their plant, I revisited some of the data.

We've always been told about barrel length and whether the barrels are vented etc. for universal test receivers with handgun data, but often this information is not all provided. This is no exception.

Well imagine my surprise to see that the max load for a 300gr in a 44 Mag with H110 and 296 producing MV below 1000fps (jacketed bullets). Well part of the reason is that the test barrel length is 4" but it still seemed low and I was surprised to see that by comparison the 4" data for the 41 Mag seems more in line with my expectations. I compared the loads to Hodgdon's website data where there is also some pressure data (8.375" barrel) and looked at loads and pressure. Whilst the Lyman data seems sound it is also in some cases 200 to 300fps slower than data for a 7.5" Blackhawk in some of my other manuals with similar bullet weights and sometimes the same bullet (i.e. exactly the same; manufacturer etc). I then noticed that the loads for the TC's were exactly the same charge and I could compare that to my Sierra and Hornady manuals with which it correlated extremely well.

This just reminded me again of how wrong you can go by assuming things, for example that loads were too low just because of the velocity and for example start at a max, when in fact it is the platform used to test, so it would seem that accounts for the difference from my expectations. Fortunately we are spoilt for resources now and I have access to data in books and articles by John Taffin, John Linebaugh, Brian Pearce, Glenn Fryxell and others, in addition to my manuals. It also shows you how important it is to take note of things like barrel length and other factors and how relevant a chronograph can be if you intend to approach top loads.

Another recent experience was my finding with IMR7828 in the 340 Weatherby, where my QL data was quite a bit below that in the manuals and where it seems that the manuals were closer to my experience.

Strangely with the examples that I looked at the 44 Magnum really stood out and I'm still a bit surprised by it.
I shoot cases with a belt because I feel the other cartridges need to pull their trousers up.

.257

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I agree, it is amazing the difference in the loads from different sources.
Also the different bullet designs. When loads x brand bullet l look at that reloading manual the closest. I have also noticed a big difference in primers.
Noticed that some manuals seem to be low all the time and others seem to run hot.
When l started reloading l had a sierra manual only for years. Never had a problem
Mike

224KING

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One shouldn't forget that their particular pistol/rifle plays a big part in this also.
Remember 10534

Sorry... Yesterday was the last and final day for any and all complaints whatsoever.

I try to avoid temptation unless I can't resist it.

Everyone has a photographic memory.Some just don't have film.

Exactly 224, and the only way to really know that is to use a chronograph.

I've had guys at the range ask to use my chronograph before and my standard rule was that I would shoot over it, as if they hit it they own it and you cannot easily replace an old Oehler here in SA. Most times they were way slower than expected. Many 30-06's shooting 180's at 2300 to 2400 fps etc. which in fact wroks great for most of our bushveld hunting. But one day a fellow came with a custom 338 Win Mag built on a VZ24 action. The first shot really surprised me as the trigger guard belted my knuckle and the velocity read over 3000 fps as I recall (it was some years ago). The second was the same and I suspected something was wrong so I enquired as to the bullet weight. He claimed that they were 230gr Rhino's (a solid shank design no less). It was before I owned a 340 but I remember thinking that he was right up there at 340 performance. There were no obvious signs of excessive pressure.

That cured me of shooting rifles of people I don't know and trust.
I shoot cases with a belt because I feel the other cartridges need to pull their trousers up.

eford

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Cases and primer cups used for lead core bullets canít take the pressures of the highest loads produced with Barnes all-copper hunting bullets. Itís a case of high loads in a Barnes manual being safe with their bullets only. Lead core load limits used with Barnes TTSX or TSX bullets is safe.
Nosler was notorious for fudging the velocities in their reloading manuals using almost the same loads as other manufacturers. Was it longer test barrels, super tight barrels, or rounding up waaaaayyyyyyy to much? I donít know what their most recent manual shows for the velocity of Nosler bullets.
Hodgdon and Hornady manuals remain my favorites.
« Last Edit: June 20, 2020, 09:52:10 PM by eford »
Of all the gin joints in all the towns in all the world, she walks into mine.

Every man needs to know his limits.

Iíve noticed where I shoot mostly ,500-800 ft elevation , velocities are always lower and pressure signs come early. I will lean towards the slower powders when possible to try and keep pressure down but case fill then becomes the hard balance if Iím trying to shoot larger bullets for caliber. Heard of guys running large rifle primers in magnum cases to offset. Guess kinda like Lapua 6.5 cm brass built for small rifle primers. Always reading about guys getting better velocities than published data and wondering if itís safe or real.

.257

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One shouldn't forget that their particular pistol/rifle plays a big part in this also.

Agree, its one of the differences in manuals. Each one of them are using different receivers and barrels, thus different starting and max loads for their set-up. No different than our rifles. Reloading manuals are a guide only
Mike