Thanks for the information on reloading my .270 Gibbs I recently inquired about.
My next question is fireforming. The way I under stand this is that I am to use Winchester .270 casings with a medium .270 load..??

This sounds a litle to simple or am I trying to read to much into this?

I am still looking for imformation and history on Gibbs rifles so if anyone can direct me it would be appreciated.

Thanks,
Max

maxwell---

The headspace datum is TOTALLY different between the Winchester and the Gibbs.

DO NOT FIRE 270 WINCHESTER AMMO IN A GIBBS CHAMBER!!

Use either 280, 30-06, or 35 Whelen brass. Size in a Gibbs die until the case fits with all you can do to close the bolt with one finger "feel".

Load with a mid-book Gibbs load and shoot it.

The reason you use larger brass is to have a headspace point when you neck it down.

Since a picture is worth a thousand words, here's a picture of what you're trying to do. I'd suggest '06 or 280 Rem brass. You want to run the larger neck diameter brass into your 270 Gibbs die to produce a "secondary shoulder" (like that shown in the middle. Then load up a 270 Win or starting 270 Gibbs load with a bullet and fireform to blow out the shoulder (like photo at right.) If you don't have 270 Gibbs data, I recommend not more than 5-10% above 270 Win loads. By all means, I would compare capacity before fireforming and after fireforming (with water or powder) to determine your actual capacity gain. In my 30 Gibbs, I measured a 10% capacity gain. If you still don't understand, ask more questions. ~~~ Lars ~~~



[ 04-04-2003, 04:19: Message edited by: Lars G ]

The only safe way to use 270 brass is to neck it up in a 280 Rem die and then neck it back down in a 270 Gibbs die. Do it as Jack described (tight fit in the chamber). You need that false shoulder to create enough headspace to fireform without blowback.

Canuck

I use 270 brass to form for my 6.5 Gibbs and it is a pain to trim 270 Win brass (it is longer). I think I'd use '06 brass for the 270 Gibbs.

Thank you all for the information. I will be resizing the brass (.30-.06) this weekend. Is there any speacial lube other than case lube or technique I should be aware of when doing this? As this seems to be alot of stain on the neck of the case going from .30 to .270.

Lars you noted out that I should measure out my actual capacity gain, does this mean that if I have an 8% increase I can increase my standard .270 load to a max of that amount?
Restasured, I would not push the envelope this soon in my wildcat education. I ask this question because the only information I have been able to find on .270 Gibbs loads was at stevespages.com, thanks to MarshMule.

Im tough skined so don't be afraid to tell me where I'm making any mistakes. I would rather find out now rather than later when my post reads " Need new .270 Gibbs and a glass eye"
Again thanks for the help and I will keep asking questions.

Max

Get some Imperial Case Lube, and put a little (a very little) on the inside and outside of the neck. You'll be amazed at how this makes the re-sizing easier. - Dan

Max - No problem helping you out! I wish I had all this on-line advice when I started wildcatting. Just a few more comments from me. You really shouldn't need much lube to size the cases. I've done the outside of the necks w/o lube, but you'd want something on the inside of the neck (graphite, motor mica, case lube) when running the expander ball back thru it. I'd suggest a little lube (imperial, WD-40, case lube) on the shoulder (old shoulder left on the '06 case) to help it blow out to the Gibbs chamber and assist in forming crisp corners on the case. Not too much mind you. Also, As JBelk, says, you want to be very carefull on how you size your brass. Just the bare minimum so you can close the bolt with some resistance.

The case capacity thing is more FYI. You certainly would not want to loader any higher (percentage wise) than you are gaining capacity wise. Me thinks that you will be somewhere between the 270 Win and 270 Wby in capacity. I know I have some articles and data on the 270 Gibbs that I will try to scan and send to you. Won't be until next week, cuz I don't have a scanner at home. Have fun and BS (be safe!)

Is there any problem using nickel primed brass for the Gibbs?
Just about all my hunting partners and myself shoot .30-.06's and this would be a good way to keep the Gibbs ammo seperate.

Max-

I'd recommend against using nickel plated brass. You will likely get cracks and flaking when you neck down to .270. If it flakes off in your sizing die you could end up scoring the surface and you will get scratches on your subsequent reloads.

I can get some data out of the Gibbs book if you like. I will try and post on the weekend.

It would be good to identify the brass to avoid grabbing the wrong ammo, but you won't have to worry about chambering the wrong ammo. 270 Gibbs wont fit in an '06 chamber (shoulder will hang up), nor will '06 ammo chamber in the 270 Gibbs (bullet will hang up in the throat).

Canuck

[ 04-05-2003, 01:12: Message edited by: Canuck ]

I formed plenty of Gibbs cases from RP nickel plated brass and have never experienced flaking of the plating. Now necks will tend to split sooner with nickel plated stuff. I really like nickel plated stuff for field loads, so it's about all I use. I don't care if I only get 4-5 reloads. The economy of reloading is recovered in the first few reloadings anyway.

I wouldn't sweat to ammo mix-up thing. NFW anyone is going to get a Gibbs round into a std chamber. Now if your buddies are idiots and you let them handle your rifle - that's another story.

maxwell---

Nickle brass has never given me a problem. I use a lot of it, too.

The reason the case capacity is important is because small charges of slow powder can be VERY dangerous.

As a beginning reloader you might be tempted to be too conservative with a slow powder and then have extra volume in the improved case and run into a problem.

The rule of thumb on any powder 4350 or slower is to never load less than 90% of a max load. This applies to ALL calibers.

Although I prefer to neck size a larger diameter down to the correct neck diameter, fireforming can also be done by seating the bullet out so that it is in the lands. That does raise pressures, and I would not use heavy loads. I have not had trouble using moderate loads as the chamber of the Gibbs ot other improved cartridge is larger and reduces pressures as compared with a standard chamber.

Jerry

Lars and Jack, Thanks for the correction on the nickel brass. I haven't tried it with '06 brass going to 6.5. I have had a lot of grief with 338 going up to 416 though, and that is what I was basing my opinion on. I have also had trouble with flaking in 375 H&H brass on the first reload, so I assumed the nickel plating was not very maleable.

Cheers,
Canuck

Canuck - I've necked quite a few 338 Nickel cases up to 375 to form for my 375 Taylor and I presume you have a 416 Taylor. Here's a few things I observed. Necking up in roughly 1 caliber increments is the best way. For me, that means 358 first and then 375 nextand of course heavily lubed inside the necks. Loss due to neck splits is roughly 15%. I tried fireforming w/o a bullet using Unique, COW and a wax plug and got 100% neck splits. These cases to not like getting neck expanded all at once. I really don't like expands necks upward so radically. Still trying to find a source for Federal 458 Win nickel plated. I know they make it for their Safari grade ammo, but I can't find it as a reloading component. If anyone knows how to get these, or even once-fired, please let me know. ~~~ Lars ~~~

Does anyone know of a gunsmith that has reamers for the 270 Gibbs? I have a 270 that I would like to have rechambered.