Higher load pressure have anything to do with actual or felt recoil on a given rifle/caliber combination?

More psi = more V. More V = more recoil. If you want a formula for recoil, pm me.
Brice

It is not that simple.
Pressure does not always have a correlation to recoil. Neither does velocity. The formulas for recoil take into account the powder weight. So, assume you used a fast powder and a slow one. More of the slow and less of the fast. Let's say that both give the same velocity, and the pressures might or might not be the same. Recoil will more in the one with the more powder. So, there is not a hard and fast rule that correlates pressure with recoil.

no, sir -- time under the pressure curve is what makes "work" .. pressure is an input, but NOT what most people think...

Here's the canny -- nearly every load in a reloading manual is about the same pressure (save perhaps the reduced loads, but that depends on the powder) .. and if rel 22 is faster with a 180gr bullet than 3031 with the same, and they are measured to stay under the SAME peak pressure, then "pressure" doesn't drive vel.

how LONG the pressure lasts (this is time/pressure curve, known as work) is what matters.

Made simple.....to the op

Yes

I stand chastened and corrected. I should have said 'Generally,". If one is using similar and appropriate powders, (appropriate for the caliber and bullet), maximum average pressures should be similar, and more powder will usually result in more velocity. If you substitute H1000 for 4895, 'twil not be so.

quote:

DPCD So, there is not a hard and fast rule that correlates pressure with recoil.

TRUE roger

As has been put above, if you don't want to think about it too deeply, then you can say "yes". Generally. Sometimes. Maybe.
But if you want the real answer, then, no.
Think of this extreme case; you are using some pistol powder for reduced loads; It is easy to quickly get some very high pressures, but as Jeff said, the curve is very short , so the bullet won't go too fast. But with a case full of slow powder, the bullet will go much faster, pressure will be much lower, and recoil will be much higher. Too much thinking this early.

Actually the area under the pressure time curve
is an impulse Pound Seconds.

The area under the curve is affected by both time and pressure. Velocity is always driven by pressure as one of the parameters. You cannot get velocity without it.

Recoil is even more complicated than that. Let's say you start with a 26" barrel and a load which develops 3000 fps. Then you cut that barrel to 22" but add the same amount of weight to the rifle as is represented by the missing 4" of barrel. You then fire the same load in the shorter barrel and get 2850 fps. The recoil will be essentially the same, although the velocities are significantly different.

There is also the fact that certain powders have more pulse than others and although differ in charge weight very little to other powders have a sharper recoil, this be true with just about every load and cartridge I've ever used with H4350.
I do understand pressure, but this phenomenon has me perplexed.

Cheers.

Using Newton's 3rd Law of motion, the action (bullet and gasses moving forward) had an equal and opposite reaction (recoil). Therefore, we calculate the kinetic energy of the ejecta, which is 1/2mv^2. So we take the mass of the bullet and powder in grains and divide that by 7000 to convert it to pounds. We then multiply this by the muzzle velocity squared and divide by 2. This gives you an energy value in pounds-feet squared per seccond squared. This is also the true recoil energy of the rifle.

Given the same gun, if and only if increasng the preasure increases the kineticic energy of the ejecta, then it will increase the felt recoil.

The average velocity of the powder gas is 1/2
the muzzle velocity (one end of the column is
not moving. What you feel is an Impulse MXV
not energy. The rate of change in velocity
(acceleration) is the force. "Sharpness" due
to the rate of change in acceleration or "Jerk".

Sometimes, one can become baffled with BS!!

Bottom line is hot loads kick more than mild loads, powder is the primary culprit..

I would hate to waste my time overthinking the difference..

quote:

Originally posted by Atkinson:
Sometimes, one can become baffled with BS!!

Bottom line is hot loads kick more than mild loads, powder is the primary culprit..

I would hate to waste my time overthinking the difference..

Seriously, Thoermonuclear Ray?

quote:

Originally posted by SR4759:
The area under the curve is affected by both time and pressure. Velocity is always driven by pressure as one of the parameters. You cannot get velocity without it.

or the most important variable, TIME --

ask yourself .. why does a longer barrel tend to produce higher velocity over a chrono, from the same loads -- comparing a 18" to a 24" for example? why.. because the same pressure spent more time working on the bullet ...

within acceptable parameters, the amount of time that the pressure works determines velocity - the amount of powder burnt (exjecta) has alot to do with felt recoil .. 10gr of too stupidly fast to be for normal loads will get your whizbannger going 1200 fps... while it takes 60gr of an appropriate for caliber powder to go that fast on your same case (its a 308x20mm fat mac - called a whizbanger)... the 10gr load has WAY higher peak pressure, though operates at less time...

the 60 gr load would kick more...

and "pressure", once inside of relevant parameters, isn't the end all be all that some would state it is.. its also non-linear in progression... though velocity tends to map closely with work...

and, yes, Dorothy, "all" of them thar loads in data daer load book for de old thirty-thirty are pretty much the same pressure - and NONE higher than the lawyer's opinion of max load -- except the reduced loads or the highly compressed as exceptions to frame the case.

it really is that easy.. oh, yeah, and the earth is round

Well, now that you've absorbed the simple part of it, I must tell you that recoil velocity is another factor, which explains why a 338 Win Mag can bites like a SOB, but a 375 H 'n H can feel like a mother's bedtime kiss. And, when the stakes get really high, as in around 505 Gibbs territory, torque begins to tear the rifle out of your mitts.

Rule No. 1: Make sure the stock fits you.