Gibbs and Mashburn cartridges.

[.30 Newton]

Hi guys.

I wondered if anyone on this forum is using the Gibbs cartridges. I'm interested in both cases and reloading data for an article I am writing.

I'm also interested in the Mashburn cartridges and info on them.

Thanks
Allan

[jeepmann1948]

P. O. Ackley's books have them listed in them, however they are out of print and getting pricey when they come up for sale .

[Reed1911]

I have experience with the .218 Mash. Bee and the .30 Gibbs. The Bee is a significant improvement and fills a gap the Gibbs no longer does which I think is a part of why it fell out of favor. That and the posted velocity gains came with pressures that I would not consider safe (in excess of 60K).

[dickttx]

Not real pertinant to the post, but the title reminded me that in the late 60's when I was getting interested in guns, I used to occasionally visit Mashburn Arms in Oklahoma City.
Mr Mashburn was usually puttering around in there or visiting with someone.  Didn't really know much about him at the time.
Later I bought P. O. Ackley's Handbooks and they are full of Mashburn's cartridges, as well as Ackley's.
Urban renewal demolished the entire area where Mashburn Arms was and I don't know if it later opened somewhere else or not.  I don't remember it after that.

[Catfish]

the Ackley book are available and can be found at different time on the major shooting supply houses. They are a great referance, but rember that all of his data was hot and with changes in powder over the years some is dangerious. When I use his data I always start down at least 20%.

[Darrell Davis]

I owned a 30 Gibbs, and it was an interesting cartridge to work with.

It, like some other wildcat or improved rounds, may not be worth the price for gains realized, but they are fun never the less.

Rocky Gibbs lived not far from where I call home, so there were a good number of Gibbs rifles in the area.

You could look for a book, "Gibb's Cartridges and Front Ignition Loading Technique" - published by Wolfe Publishing Co.   ISBN: 0-935632-99-9

This publication gives a lot of useful info on the Gibb's live of 30/06 wildcats.

Rocky lived the next house over from some in-law relation, but being young I never made contact, a fact I have been/am sorry for.

If I can provide any info from my copy of the book, let me know.

Keep em coming!

CDOC

[.30 Newton]

Thanks for the info guys.

I do have the Gibbs book, and it is an interesting read.

But I am also looking for somenone who uses the cartridges today, and I am espically looking for the .25 and .270 Gibbs.

[lgm270]

I once read something interesting about the .375 Mashburn, based on the .375 H&H case.  It would  chamber and safely fire .375 H&H or .375 Weatherby  rounds, which gave it a measure of flexibility and versatility  unmatched by any other .375 round. 

[gman628]

You may want to do a search on the Cooper Express line of cartridges.  Neal Cooper has an extensive line of cartridges that are basically a Gibbs cartridge with a rim designed for single shot guns.  His first in the line was the 30 CE, then the .338 CE, now I believe there are many more.  I own a .338 CE in a 16" Encore pistol barrel myself.  I beleive McGowen is chambering the barrels and C&H makes the dies.  the cartridge is formed from a 7 x 65R case.  Below is a 338CE cartridge (left) and a 30-06(right).

Gary

[Darrell Davis]

Well igm270, your posting does indicate a lot of versitility in that cartridge, but it is not totally unheard of with a good number of other rounds.

For example and "improved" cartridge such as those by P.O.Ackely, could be fired in a standard chamber - 270 Win. in a 270 AI chamber, standard 243 in a 243 AI chamber etc.

Then there is the common use of the 300H&H being fired in the 300 Weatherby chamber etc.

Of course when the "standard" cartridge is fired in the "improved" chamber they are fire formed and come out of the chamber not as a standard case, but as an improved case.

But then, I suspect you knew that already.

AS a side note. If someone desires to have their rifles chamber "improved", find a gunsmith that knows what he is doing.

The improved chambers such as those by Ackely, are reamed ONLY!!!! to the point where the bolt will close on a standard cartridge, with a slight crush fit.  This assures proper head space.

The 30Gibbs I owned, had been reamed overly deep, which gave a very short neck and a shoulder which was even farther forward then a normal 30 Gibbs.

However, condidering this was a "wildcat" and not an improved cartridge, meaning brass needed to be formed - normally with a method other then fireforming -, It was no big thing.

I figured I had kind of an "improved" wildcat, or maybe a wildcat wildcat.

Keep em coming!

CDOC

[Gibbsfan]

I shoot a 270 Gibbs and it is my favorite elk rifle flat shootn and really deadly. Took a elk this year at 750 yrds with 4 witnesses. By far and away my favorite. I have it chambered in a tc encore prohunter. Never thought it was going to be as accurate as it is but it thinks its a target rifle.

[Darrell Davis]

Hey Gibbsfan,

Do you live in the Moscow, Idaho area?

Because of Rocky Gibbs living just a few miles from Moscow, there were quite a number of Gibbs rifles in this area.

Personally, wouldn't be afraid to have another "Gibbs" although the Gibbs' rounds below 30 cal. would be a bit easier to make brass for.

Mine, the 30Gibbs, would have been a good one to use 35 whelen brass to start with, but I just used "06" brass, long seated the bullet into the lands for the fireforming shot, and went from there, no problem.

However, as I noted earlier, my Gibbs chamber was even longer then standard, so if I were to have used cases fireformed in another 30Gibbs chamber, there would have been a head space issue, for sure!.

You probably know, that the 270 Gibbs is where Rocky really started with his line of widcats.

If you don't know the story, let me know and I'll spin the yarn your an everyone's pleasure.

Keep em Coming!

CDOC