Is anyone running an 8mm Gibbs?

I have been thinking about reaming my 8mm-06 to a Gibbs. What sort of velocities are you getting with 200 and 250 grainers? Will the Gibbs reamer clean up in an Ackley chamber?......inquiring minds want to know...

Roger

About 1.5% velocity gain

Yes a gibbs should clean an AI chamber body. Not sure of the neck

source formed brass first!!

assuming that you have already used rel22 in your 8-06ai .. there's no real gains to be had for the hassle

Sorry, I was not clear in my opening statement.....my VZ24 is an 8mm-06 not Ackley, the Ackley question was only curiosity.

Roger

The Gibbs is highly over rated and requires a long tube and hot loads, plus forming cases is a damn nightmare...Your better off where you are with a 8mm-06, but if one must improve that then the ackley is the way to go, forming case can get expensive..My go to elk rifle is a Brno mod 21 in 8mm-06 Ackley Imp., its an elk killer for sure and mild of recoil and accurate as can be..I like it a lot..

This may be a source of brass. I say may bc I have never used them.

https://www.rccbrass.com/8mm-gibbs/

Ray, I have had good experiences case forming my brass in 30 Gibbs. Using 06 brass I open the neck to 35 cal. then resize mouth back to 30, getting a dbl. neck wrinkle then load a minor case forming load, fire in Gibbs chamber + you're there. My only complaint is the short brass life.

The same could be said of the 8MM Gibbs. Also made from an 06 case ( we ALL have beaucoup in the loading room as mother cases after trimming. The same principle applies. After trimming to length, open to 35 then resize neck to 8mm,(anneal if you find it necessary) fireform + you have your brass. I built my 35 opening spud, but you could use one from a Whelen or any other 35 cal. + then you have your base case. Also if you intend to go with an AI, that also will be done in one firing in the chamber. Easy as falling off a log.

Gibbs sold me a hydralic case former, put a case in it fill with 30 wt. oil and hit the plunger with a small sledge hammer..Oil goes everywhere on your clothes, in your hair, all over the floor..very intertaining trying to get it to work...

I formed cases the old fashion way but it was time consuming as compared to the 35 Whelen, or 8mm-06 std or Ackley..I presently have a 8mm-06 Ackley, The 8mm-06 suited me best it was matter of reloading a 06 case in a 8mm-06 die..My basic problem is Im not a wildcatter anymore..You Have to love it to enjoy it!

Gibbs cases are no bigger problem to make then anything else.
I have a 240 and a 6.5 Gibbs. Set the shoulder for gibbs length, fireform.
With an 8 gibbs, neck up 06 brass to 35 cal. Size the neck to 8mm, setting the shoulder to a slight crush fit, you have a double shoulder look. Fireform to proper shape.
I find the gains to be more worthwhile then just doing an Ackley imp shoulder.

Thanks Tony, my 8mm-06 is one that Larry cut for me, so I'd like to keep it as is but with a bit more mumbo ( more horsepower )
Everything I've read tells me that case life is pretty good....any thoughts?

Roger

I have found case life from any of the imp cartridges to be very good. Short case life would only come from to high a pressure loads. Most imp cases can be a little tricky as they don't seem to show sticky bolt lift until pressures are higher then they should be.

quote:

THE ACCURATERELOADING.COM WILDCAT FORUM

Maybe Im just mad because I bought his hydralic case former and got caught in an oil slick!

Ray, I can understand that. I recall you mentioning it before about your troubles with it. But doing it with the taper 35 spud then reneck to 30 (or 8mm) + fireform is really a breeze.

quote:

Ray, I have had good experiences case forming my brass in 30 Gibbs. Using 06 brass I open the neck to 35 cal. then resize mouth back to 30, getting a dbl. neck wrinkle then load a minor case forming load, fire in Gibbs chamber + you're there. My only complaint is the short brass life.

I have to know the length of the chamber from the datum to the bolt face, why? Because, yes just because.

If I know the length of the chamber from the datum to the bolt face I can adjust the die off the shell holder to increase the length of the case body from the datum to the case head with a feeler gage. Same for case gages; nothing improves the reloaders skill with the case gage more than the feeler gage 'with' the straight edge. the straight edge

No one ever mentions the action they are using, they never mention if the action is control feed or push feed.

I have fired cases with .127" clearance meaning the length of the chamber was .127" longer from the datum to the bolt face than the length of the case from the datum to the case head. by .127".

F. Guffey

I have had a 240, 7mm, 30 and 8mm Gibbs. They are more trouble certainly than the majority of Ackley rounds, but not that bad. I can understand the troubles with hydraulic case forming, it's very tough to get a good seal. - dan

Some of the old articles I read about Rocky were pretty bad.

Meaning his method was to run the pressures up way high to obtain his claims.

It was said that when he was on his death bed he ordered his wife to burn all of his notes and loading data. Which she did.

I would not touch his creations without having access to pressure testing equipment.

Here ya go, strain gauge mounted on a test barrel. 20 foot lanyard on the trigger. I positioned the truck between myself and the shooting bench when yanking on the lanyard. Holes in the truck are easy to fix, in my hide, not so much.

I would choose 8x68 over the wildcatted stuff.

quote:

Originally posted by ramrod340:
About 1.5% velocity gain

Yes a gibbs should clean an AI chamber body. Not sure of the neck

You could do that with a couple more inches of barrel.

quote:

Originally posted by ramrod340:
About 1.5% velocity gain

Yes a gibbs should clean an AI chamber body. Not sure of the neck

Damn, where you been? Have not read any posts by you in a gator's age.

I sold the duplicator to Sonoran Gunstocks in Tucson.

The 8x68 is a unheralded wonder. Its just got to be the best of the 8MMs...But the Gibbs and Ackleys are fine, I never said they were not. I said I didn't like case forming, fireforming or any such creative stuff and simply because the day of the need for wildcatters has come and gone, and today its only entertainment, not a bad thing, but not for me in my last chapter...I still have a couple of simi wildcats like the 8mm/06 Ackley., 6x45 sorta wildcatty, and an annealer I got from Norman, that actually isn't getting that much use, but handy when you need it..If I had it to do over, I would have remained loyal to the 8mm/06 that extra 5% that amounted to about 2.5 grs more powder and less than 100FPS in most cases, and less than 200 fps with any load so it didn't change a thing that I could tell on the animals Ive shot with it..In fact the 8x57 or 8x60 accomplished the same results before I got to tinkering with that caliber..but today its worked its way up the the 8mm/06 Ackley and it was more trouble than its worth but the cases are formed and a couple of coffee cans full of Ackley formed brass and twice that many of those ackley cases are loaded and ready to go and the freezer is full of elk and soon some Texas whitetail will be in there..Love those Texas Hill Country whitetail, the best meat yet!!

I have had a couple 8x68 rifles and still have one. Very capable cartridge. Isn't much it won't put on the ground with a 200 gr Partition or a 200 gr TSX.I also have an 8mm-338. It has the very same case capacity as the 8x68 . My 8x68 and 8mm-338 take the same loads and deliver the same velocities according to my chronograph. 338 brass is a lot easier and cheaper to come by than 8x68 brass but whatever floats your boat. I also have another 8mm wildcat . It is the 9.3x64 case necked down to 8mm.Called the 8mm Mazon case capacity is a couple grs less but velocity is within a few fps of the 8x68 and the 8mm-338. All 3 are less than a 100 fps behind the 8mm Rem Mag with a lot less powder and recoil

I much prefer the 9.3x62 to anything else, the 9.3x64 is a better caliber but also recoild more, and these days I don't like recoil like I used to. I like the 8mm/06 better than the Ackley version, but not willing to give up that pretty small ring Brno mod 21 in the ackely..They are all good rounds and not a hell of a lot difference between any mentioned so far..and yes the 338 Win is probably the king of the hill..