Possible tip or BS?

In talking with a big bore hunter/seller/reloader, he is "Recoil sensitive". When you shoot guns like 577 Nitro Express! Even at 12-15 pounds it still kicks.

Ok, his tip is that if you find less powders that can get the same FPS you will have less kick from a load that asks for 50gr than a load that asks 70gr. He says it has more "push" than "pow." This load is just an example.

He also likes an old powder IMR3031 for most of his long guns.

What do you think?

There is definitely a difference in burn rates that effect felt recoil impulse.

In larger case capacity cartridges, I can feel a difference between H1000 and N570 when pushing the same weight bullets at the same MV. H1000 is far "snappier" or "sharp", where N570 is more of a "hard push".

Although, I don't see any powder that takes 50gr to match velocities of another powder that takes 70gr to get the same MV as being even possible. 20gr is a HUGE difference, even for different powders. Maybe 80 and 100gr in some of the big capacity magnums? Even then, probably not.

There are also certain case designs that seem to do the same thing. For some reason, the .300WSM always seems sharper to shoot than a comparable long action cartridge pushing the same bullet weight at the same MV in a same weight rifle.

lancetkenyon said:

There is definitely a difference in burn rates that effect felt recoil impulse.

In larger case capacity cartridges, I can feel a difference between H1000 and N570 when pushing the same weight bullets at the same MV. H1000 is far "snappier" or "sharp", where N570 is more of a "hard push".

Although, I don't see any powder that takes 50gr to match velocities of another powder that takes 70gr to get the same MV as being even possible. 20gr is a HUGE difference, even for different powders. Maybe 80 and 100gr in some of the big capacity magnums? Even then, probably not.

There are also certain case designs that seem to do the same thing. For some reason, the .300WSM always seems sharper to shoot than a comparable long action cartridge pushing the same bullet weight at the same MV in a same weight rifle.

Click to expand...

Let me change my post. I was just PFA (pulling from air) about the 50gr-70gr. Just my "example". Probably 80gr-100gr as you stated.

But maybe there is some truth?

He's right in that yes, a lower charge weight reduces gas ejecta volume, and does impact the recoil calculation.

But bullet weight and rifle weight have a much larger impact on the calculation. I did a quick deal, and using 30-06 as an example - dropping from 180gn bullet to 165gn bullet, or adding 2# (10lb to 12lb) to rifle weight) each is the same as dropping 20% of charge weight. Only one of those variables (powder) has a direct impact on precision, so it can be more difficult to arbitrarily change.

You can skin the cat multiple ways. His theory basically amounts to use less of a faster powder, which has a range of application.

Anecdotally, I would also say there's a pretty big difference between 90% loads to max loads also. I rarely shoot for max pressure/ max velocity, I shoot for precision and if I need more velocity would upsize the case rather than keep stuffing it with powder. Basically trying to say if I set up a 300 WM and 300 RUM to push the same bullet at the same velocity, the 300 RUM should have more recoil because it does use more powder (generally), but being a less-than-max load impulse feels different than a max load 300 WM. I haven't done this exact comparison, but I shoot a lot of 300 RUM that's not maxed out instead of loading 300 WM, makes the one rifle more versatile to me, and the RUM is consistently more comfortable to shoot. Even in same stock/ etc - I use factory Rem 700 Long Range rifles in 300WM as a base to convert to 30 Sherman and some other non-factory cartridges, so I have essentially the same rifle in 300 RUM, 300 WM, 30 Sherman to compare against. (I did put a JP tank brake on a 30 Sherman and it might as well be a 308 now Unpleasant for everyone except me!)

One example per Nosler to build that out with numbers:
300WM, 200gn AccuBond, Magpro - 2935FPS @ 80.0gn/ 105% load density (middle load on their chart, not max)
300RUM, 200gn AccuBond, Magpro - 2946FPS @ 86.0vn/ 86% load density (bottom load on their chart)
The RUM, because of more case space impacting burn, uses more power to achieve the same velocity. Yet subjectively to me, the higher charge weight would have a lighter/ different impulse compared to the 300 WM load.

Then there's the issues of powders don't carry over to a larger case, so what would 82.5gn of H4831SC feel like in the RUM to make the same velocity but at an 82.5gn charge weight?

So much about recoil is subjective, stock design and fit are a huge part of it also.

Marplot said:

Let me change my post. I was just PFA (pulling from air) about the 50gr-70gr. Just my "example". Probably 80gr-100gr as you stated.

But maybe there is some truth?

Click to expand...

Absolutely! If you run a recoil program for a cartridge, the powder weight is factored into the equation! memtb

In my sons 28 Nosler there is a major recoil difference with 162's at 3350 between RL 33 and RL 26, I don't have my notes handy but I recall a difference in charge weight of almost 10 grains, RL 26 being the lower charge weight and significantly lower felt recoil.

Totally disagree. In my big bores, most are doubles, 15-18 pounds. Using full power loads, recoil is vastly different with different powders.
My 505 Gibbs was a bolt action, 9lbs fully loaded. Kicked so hard it was painful!
Recoil pulse is determined by burn rate rather than powder amount.
In all of them, recoil is sharper and harder using H4350 over anything else, including Retumbo and even H50BMG. Using 760 instead of H4350, recoil is reduced significantly. When I load pussycat loads, using fast powder and fillers, even they will change recoil depending on which powder is chosen. H4895 is soft recoil, shotgun powder is fast recoil…

Cheers.