All this talk on the 505 Gibbs is driving me nuts. I have not receive my rifle yet, so do not know what is like to fire one off, and am sitting here with brass, bullets and Quickload, so at least i can shoot in wizard land.

So I got to thinking, what is it about the Gibbs, other than raw ftlbs., that makes a reputation of a big bore that is hard to shoot well. And with all the interest in the 458 Lott, it seems that this is also hard kicking but I not to the level of the Gibbs, why not? So I ran some Quickload sims (man, felt good to shoot these two ) and compare the results.

Obviously, the photo is of some cowboy touching of a 505 Gibbs.



The plot shows chamber pressure over time for the 505 and the 458 Lott, with the same loading conditions (except powder charge) using IMR4831, 500g bullet and 24" barrel giving 2294 fps for both.

I am speculating, but I think these two curves might explain the reputation of the Gibbs. Other than the peak pressure difference, I think the longer pressure rise time of the Gibbs vs the 458 Lott and the Gibbs higher, longer pressure tail, could be the answer. I wonder if the human body cannot respond to the sharp 458 Lott pressure rise thereby giving a more stable shooting positon whereas the long pressure rise of the Gibbs gives the body time to respond, call it flinch, making a less stable platform. Also, the high, long pressure tail of the Gibbs says that it keeps on pushing the body longer than the 458 Lott, unbalancing the body.

So, I wonder if the long, slow push of the Gibbs and its higher muzzle pressure allows the human body to react more compared to the sharp jab of something like the 458 Lott and this, other than ftlbs, contributes to the shooting difficulty.

regards,

steve

Steve,
the picture does NOT reflect reality...

my 17 year old son, who's nearly 8 inches shorter than me, shoots my 500 jeffe and the barrel doesn't rise HALF that much... we video'ed me and a gumbha (my name for a SUCKER that thinks he can shoot anything, and hasn't shot one bigger than 338)...

the gumbha's barrel rised about 12-16 inches...

mine, perhaps 4....

he was nearly my height and build

my son's shooting is only about 10-14 inches...

NOT the 30 inches or so for this cowboy (is it elmer?)... this guy would be far better off with a 375, as his second shot would be 10s of seconds away.

they DO NOT kick like you think they might... but when you get to ignoring them, and have scoped them, you WILL get a weatherby brow

jeffe

Thats elmer all right and I gotta agree with you about the barrel rise. I don't know what he did at the time of that picture but either he's puttin on or that gun weighs about 6lbs Me thinks the gun writers like to do that sometimes. I saw a pic somewhere of somebody shooting a ruger #1 in .416 rigby ( the same gun I have ) and at the shot the barrel goes about 2 feet in the air. I'm 6'3" and a slender 150 lbs and my rigby rises no more than 7-8" at most. I htink it's alot of show.

I have noticed a trend in magazines and books, with regard to, the muzzle rise of the true big bores. Starting with the 50 calibers and continuing on up every published picture shows the muzzles pointing straight up upon firing. I don't think the muzzle of my unbraked 500 A Square rises more than 4 - 5 inches! I am shooting 570gr Barnes X bullets at 2380 fps too! Far hotter than any 505 Gibbs factory load.

Lucs

You guy's got it all wrong in the second picture Elmer's shooting at waterfowl

It's a DDR he's got there.
Dangerous Duck Rifle

Besides all the mumbo-jumbo about pressure rise, which I would doubt anyone would notice, the ft-lbs for the Lott about 5800 and hence the Gibbs:

5800 x 525/500 = 6090, or there abouts. 5%.

On the other hand the Lott is my limit, but maybe 5% more is not that much.

The muzzle rise has more to do with the drop of butt on the rifle than anything else. The factory CZ550, before I had it McMillanized, was almost as bad as the photo.

I should add that Richard Harland noticed a black and white difference between the 458 Win. MAg. and his .505 Gibbs, as did Tony Sanchez between the .416 Rigby and the 500 Jeffery. Maybe energy, maybe bullet weight, maybe both. Seems to be a breakover point there somewhere around 5500 ft-lbs. and 500 grains.

[ 11-16-2003, 00:03: Message edited by: Will ]

Will, you are right on.

With the typical drop at heel on a pre-war British or European DGR, that kind of muzzle rise would be the rule, not the exception.

THE key to handling heavy rifle recoil is stock design--it's just as important a factor as more weight, IMO.

I'm not sure whether they are the same thing or not but recoil velocity is a major factor in comfortable handling of recoil. That's why I find the recoil of a .338 much more unpleasant than that of the .375, even though the recoil energy of the latter is greater.

Stock design is, indeed, a major factor. The worst recoiling rifle I ever shot was, if you can believe this, a 30'06 in a featherweight barreled action and a synthetic Weatherby stock. Ouch!, that little bugger hurt.

In either case, a 10.5 lb. .505 Gibbs with a good, long, straight stock; a wide butt and a fat pad (and maybe a couple of mercury buffers for us chicken types) shouldn't be too hard to get used to. Just don't try to do it all at once.

BTW, Elmer wasn't very big. Thus even though he was one Hell of a shot and loved large calibers, they did tend to shove him around a little.

Keep in mind the size of the powder charge. The Lott provides the noted ft.Lbs. while burning far less powder than does the cavernous Gibbs. Modern handloads make for a more realistic comparison. I've used the Lott with 500's @ 2,330 fps and the 450's @ 2,450 fps. I've fired the Gibbs with the 570's & 600's @ as high as 2,500 (2,325fps being my hunting load) and can tell you the difference is quite distinct. Another class, IMO. Even with 600 grain monolithics, the Gibbs casing is still a bit larger than need be.

[ 11-16-2003, 04:30: Message edited by: Nickudu ]

Energy expended lifting the barrel is energy not going into your shoulder.

[ 11-16-2003, 04:53: Message edited by: Nitroman ]

SOME COWBOY!!!! Thats Elmer Keith man!

Elmer must have just gotten through a tough Montana winter in his younger days and was in a weakened state, or he was just hamming it up, letting things get out of control.

I find the "shotgun"-drop at heel of a double rifle in 470 NE (500 grains at 2125 fps), or a CZ 550 humpie in 378 Wby (300 grains at 2900 fps) or my 45 Lapua humpie (500 grains at 2400 fps) ... all rifles weighing about 10.5 lbs in recoil ... to be quite comfortable. That little bit of muzzle rise does gentle the rearward kick, and it all gets smoothed out and controlled by getting a good grip on things.

Two other rifles have put me at my limit of "fun." Both have minimal drop and straight combs, and both weigh 10.75 lbs in full straight back recoil:

470 Mbogo (500 grains at 2685 fps)
500 A-Square/.510 "JAB" (570 grains at 2405 fps)

No Muzzle brakes, hate 'em.

Both of these give my right hand an electrical shock paresthesia occasionally, by pounding the brachial plexus, if I am too relaxed in the shoulder when firing. Bunching up the muscles of chest and shoulder, and a good grip with hands as well, is the secret to comfort and control.

Now, everyone who is pained by the CZ humpie needs to get down and give me 60 pushups in less than two minutes. Then you can walk the walk as well as talk the talk.

Dear Ol'Elmer must have been puny the day that photo was taken. No way is it that bad for a competent shooter.

Hey Ron,
Load that 470 down to 2300 and it's plain fun to shoot...

jeffe

Nickudu,

Let's see if I have this right. Shooting a 600 gr. bullet at 2500 fps? And it kicks like hell?

You are now a graduate the the School of the Blatantly Obvious!!

How in the hell you manage to shoot such a monster I have no idea!!

Jeffe,
The load that I settled on for the 470 Mbogo is 500 grains at 2500 fps, plenty tolerable and most uniform and accurate. 500 grains at 2300 fps would be good, clean 470 Capstick fun, eh?

I have never seen that kind of muzzle rise, except from Elmer who had a tendency to over do most things...

An English gun is designed to bring part of the recoil rearward and some of the recoil upwards regardless of what one reads from the lovers of the American classic which brings ALL the recoil stright back and hammers the living bejesus out of you....

A chacun, son gout.

Just like my whisky, I'll take my recoil straight back. Quicker for the refill and the follow up.

Ron,
Mike and I ran his to 2300, using hawk bullets and surplus wc852... and it was PLEASENT to shoot. As we had expected to hit 2400 (you just NEVER know with surplus powder, so safe and sane load dev is critical) and would restart dev... but, since it's in the major player ballpark, we went ahead and adjusted the sights for 2300...

perhaps soon we'll try to hot rod it...

jeffe

500 grains at 2300 is enough for charging blue whale down on the beach. Anything over that is, IMO, just showing off. O.K., there are exhibitionists out there who have fun showing off. Good for them. Have fun. Don't get hurt. Me, if I ever do build a Gibbs, I'll stick to about that same amount of oomph, 5800 ft. lbs of free recoil. Even a 'nelephant won't notice anything more and sauropods have become quite scarce lately.

"Both of these give my right hand an electrical shock paresthesia occasionally, by pounding the brachial plexus, if I am too relaxed in the shoulder when firing. Bunching up the muscles of chest and shoulder, and a good grip with hands as well, is the secret to comfort and control."

Ditto that. 'Cept the first time with me it was my whole right arm. I was too used to "elbow out" forming a cup for the butt. That'll never happen again. Took 1/2 an hour before my fingertips started tingling. Thought I'd hurt myself bad. Scared me. Changed that P.O.S. Pachmeyer recoil pad before I fired the next round.
I load the 600's at 2300 or 2325 or so and it is not a pain. Use a case full of H-4831 and it is 2200fps and good clean fun.

As OldSarge said:

quote:

---

I'm not sure whether they are the same thing or not but recoil velocity is a major factor in comfortable handling of recoil. That's why I find the recoil of a .338 much more unpleasant than that of the .375, even though the recoil energy of the latter is greater.

---

That was the point of my speculation. Since the pressure curve vs time translates to acceleration of the rifle, is the recoil of the Gibbs "felt" differently than say, the Lott, given same stock design, load (add additional weight to the Gibbs rifle for the extra powder). etc.

I think what I get from this discussion , from those that shoot the Gibbs, it sounds like the early reputation for recoil nastiness was probably due to sheer ftlbs, maybe in light rifles, and not much to due with recoil acceleration curve and the body/mind reactions. I agree with Oldsarge that there must be some influence, the question is, how much?

Anyhow, thanks for the discussion and I will see when my Gibbs is completed.

Thanks,

Steve

[ 11-16-2003, 21:26: Message edited by: steve505 ]

Steve,
Some of these 10 to 11 pound big bores and hot loads will have higher recoil velocity than the smaller bore and lighter weight rifles. I have never experienced any severe recoil with any rifle below .375 caliber.

Good luck with finding your sweet spot load for the .505 Gibbs. Muzzle brake in the field is a no-no. Muzzle brake and bags of lead shot at the bench is a yes-yes.

It seems that the max pressure and max bullet weight loads get vicious with just about anything bigger than .375 H&H, if the rifle weight is kept portably sporty.

It seems that muzzle pressure on an unbraked rifle might have something to do with perceived recoil, but we have chased that tiger around the bush before, in these forums, inconclusively.

Jeffe,
Of course anything over 2150 fps with a good 500 grain bullet of adequate penetration is more than enough. I finally came to the conclusion that 2500 fps in the 470 Mbogo was the sweet spot for my rifle, just like Dave Estergaard recommends in his creation.

Roger,
A-Square ... The new Jim Smith company ... It's Alive! ...
If they can bring some readily available good brass to market with the 500 A-Square headstamp, well, my barrel will have engraved on the right side:
"500 A-Square"
to go with the
".510/460 Weatherby Improved JAB"
on the left side.
I will keep tabs on the 500 A-square brass. It might be available next week. They are testing it now, and they make it in Jeffersonville, Indiana, just a drive across the Ohio River for me. Easier to get to than Horneber in Germany.

<just got back from a GREAT range day>

After watching my youngest son, 17, and about 5'8, and MIGHT weigh 145 with rocks and a rifle, shoot my 500 jeffe (535 woodleighs at 2350) and seeing the barrel rise, oh, 7 inches... I know elmer was just showing out.....

jeffe

I have a 505 Gibbs, I've shot it with 600 gr bullets at 2500 fps and yes it kicks, but the muzzel doesn't rise like that and it's still totally manageable. -Rob

This is the reason for my website to get some of the mith out of Big Bores. The picture of that rifle in "full recoil" is exaclty what scares off new shooters. The 505 being a killer to shoots just doesn't make any sense with the factory ballistics but you read about shooters with broken collar bones. Think of how many people actually had or shot these rifles in those days. I think that there are more experienced big bore shooters now than ever and it's only getting bigger.
As well as stock design a good recoil pad will make a huge difference is felt recoil by spreading it over a longer time line and softening the recoil velocity. Personally I think when your in the 80 to 90 ft.lbs. of recoil it's pretty hard to tell if there is any difference.
It's interesting to see videos where a guy shoots his rifle for show and there is the big recoil rise and body roll but when he has to make a shot under pressure there is very little muzzle jump with the same rifle.
Take good care guys,
Dave

Jeffeoso,
That young man keeps shooting those big guns and he will remain in second grade, I told you that last year...Thats why you didn't finish Sunday school, your brain is loose in the upstairs barn, besides you, like me will soon be a paraphalegic from the armpits up....Think what your sons will be by the time they are 21!!!

I can see it all clearly in my chrystal bowl...it goes like this:

Papa Jeffe can I chute da gun, OK, Ok, can I, can I, duhhhh???

What gun, whats a gun? huh! Got Aspirin, huh/

YOU HAVE BEEN FOREWARNED

Thanks Ray I got home from work, kinda tough day, and checked this thread complete with your words of advice and now my days okay. Thanks

steve

Ray,
he's 5'7, and well, kinda a runt for the family, as *I* was in second grade and that age.... LMAO.. what a great post...

as for sunday school... perhaps is was a gun... or a bevvey of girls that were the problem?

wine, liquor, song, and hunting.... throw women in on that mix, and a feller just aint got no blood left for his brain

jeffe