Home Forums Reloading Big Game Rifles Over book max loads - taboo topic?

bald hunter if we mess around enough we will bump into this stuff fairly often.

That is so true.

Yep, if you fool around long enough with enough rifles and manuals, you will run into scenarios that are only determined by the chronograph.

I ran into this with a custom barreled 7mmRemMag about 7 years back.

Long-throat 7RM

I now shoot 69gr of RL22 under a moly 160AB in this rifle for about 3,000fps. That's 6-8gr above book max, depending on the manual. The moly maybe eats up a grain or so of that, due to the loss of friction, but it is still not a load I'd drop in any other rifle. This one has a lot of freebore, and as a result, requires powder charges close to 7mm Weatherby levels. It shoots so well, I don't want to mess with getting a new chamber cut, so I live with the jump and the larger appetite for powder. Live and learn.

This is why it's tough to say there's a "standard load" for any chambering that is up near top-end levels. Two rifles in that chambering may be able to tolerate that load, or they may not. It's best to work up over a chronograph if you think they are warm loads.

I saw an interesting one just this last week when looking for data. I'm tinkering with a deer/hog load in 338WM, something that might kick a bit less than my standard 200gr/65grRL15 load. I have heard about 57-60gr of H4895 being good with 200gr bullets and making 2700-2,800fps. As I have some 185TTSX bullets coming, I wanted to see how the lighter weight bullet factored in on that front when it comes to recommended powder charges, so I went to Hogdon's online data. Max load shown for the 200gr Speer with H4895 is 62gr, with the 210gr PT at 60gr. That makes sense, with the PT being a bit heavier and having the differing internal structure. But the 185TSX has a listed max of only 59.5gr. That's a half-grain lower than the 210PT load with a bullet weighing a full 25gr less. Likely has to do with case capacity and the length of that copper 185, but still, it shows that not all bullets behave the same way. Some powder charge/bullet weight combos are obviously not just plug-and-play with any bullet of your choice.

That pretty much sums it up.

Is that just the maximum load listed in that manual, or does it take into account the "lowest maximum" in all sources?

I only consider info from the bullet manufacturer's manual, other sources data may or may not concur. I like to keep my reloading endeavors simple, if a load gives me the accuracy I'm looking for and gives good performance on game I call it good.

Sounds awfully sensible.

If you're relying at least partly on chronograph-watching, there's one problem with using only data for that bullet: More than one bullet company works up loads in a pressure barrel, then chronographs them in a factory rifle, which often results in lower velocities. A few years ago this technique resulted in one manual listing higher velocities for the .308 Winchester than the .30-06.

Speer 13? comes to mind.

I hear you - but can't get past the apparent anomaly in their own data. Look at the 7 WSM data for a 150. IIRC the WSM hull holds 82 gr water, the RM 84. The RM hull MAP pressure is 61 kpsi, the WSM 65. Nosler data denotes 4.5 gr difference in case capacity likely due to deeper seating of bullets in the WSM hull. But the MAP is also 4k higher for the WSM hull. They should be ~ same-same. I've had 2, 7 WSM and they actually ran a bit faster on average than my 7RM using like barrel lengths again likely due to the MAP differences and trying to stay on the safe side of pressure. Using Noslers own data, the WSM only runs to 3136 which is in line with other data sources on both the WSM and RM. They also had the same Wiseman barrels.

I also note their data on the fastest 7WSM load is 73 gr Magpro for 3136. Note the corresponding data for 7RM Magpro 72.5 gr for 3129. This makes sense to me because it is consistent and in line with other data sources. I first noticed this in their 30-06 data running a 165 at 3000 ft/sec with Re 22. Despite trying several lots of Re22, I could never come close to those vels in several 06s.

For IMR 4350 and 4831, they run 2.5 gr less in the WSM but seem to lose 200 ft/sec compared to the 7RM. That doesn't seem to mesh with other data and my experience.

At the end of the day, I don't find comfort in chasing their velocity, or anybody else's, that is significantly out of line for known components. New powders and technologies with pressure testing, I'm in. Same components I've been shooting for 35+ years not so much.

Just because the barrels are from the same manufacturer does not mean they are the "same".

Most of these discrepancies will be barrel or pressure related.

There are SO many variables accounting for relatively minor differences in pressure and velocity.

The BIG difference of course is that we are "guessing" our pressures when we look at a chronograph screen.........Nosler isn't.

Which cracks me up when you look at their ballistic coefficient numbers.

Specneeds: I load for many dozens of Rifles (both big game Rifles and varmint Rifles) and a few pistols that shoot Rifle cartridges.
To my knowledge I only load for and shoot 1 (one!) Rifle/cartridge that is OVER book maximum.
That Rifle is a Remington 700 in caliber 7mm Remington Magnum.
AND... the loading I decided on was just at "book maximum" back in 1985 when I started load testing for that Rifle!
That loading is NOW over book maximum (Nosler Reloading Guide (Manual) #6.
Not much good can come from habitually loading over book maximums and I firmly stay away from "pushing" pressure limits or "hot-rodding" my loadings.
Safety and accuracy are my prime objectives in handloading for my Rifles.
Hold into the wind
VarmintGuy