240 Gibs Question

Cost- as much as you want to spend
Bullet velocity- fast
Range- way out there

Honestly, the cost is going to be determined on if you have an action for it already, what barrel you want, and the cost of labor for putting them together.
As for velocity have found some data online (not always the most reliable)
75gr-RL22/63gr=3665fps
85gr-RL22/61gr=3469fps
105ge-RL22/57gr=3224fps
That is with a 24in barrel 1-12" twist.
and for range...well that will be as far as you limit yourself too. I don't know how much help that is, but I was looking at the 6.5 Gibbs for a while, but decided that when I do build a long range gun I will go with the 6.5-06 Improved. Not quite as many steps in forming the brass.
 
Not sure what you mean by "cost"....if the smith has a reamer, it costs the same to build one as with any other chambering. Dies are custom if I remember correctly.

Mine came ready to shoot, loads tweeked, dies, everything. It was done by someone who's a master, who very few people even know, a guy I'd choose over anyone anywhere to build me a gun if he were still doing that sort of thing. The moderately conservative load is 61.0/IMR 4831 and a 70BalTip @ 4100. It's one-hole-group accurate. The gun was set up with a rangefinding reticle of his design and a trajectory chart for that bullet at that speed. The cartridge is capable of more. I believe Chris at PacNor was shooting bullets (don't know what weight) at 4500 with his Gibbs. With 28" / 1.250" straight tube, 13" twist, braked barrel there's no muzzle rise and it turns rockchucks into a huge mess. Speed kills. At 660yds one chuck stretched out prone flipped end over end with at least a foot of air underneath. It's not a gun for prairie dogs or any kind of volume shooting. In 17yrs I've only put a couple hundred rds. through that gun.

The downside is die cost and making brass. This thing uses an '06 basic case that's necked down and blown out to the absolute max with a very short neck. Making brass is a hassle. The .240Gibbs has impressive performance but it's an oddball chambering. Most people haven't even seen one. I read an "authoritative" treatise about it by someone who'd never had one. Honestly I'm not sure this cartridge is worth the trouble. When I used past tense it's because the gun now has a 6mmAI barrel, a chambering that can also do 4100 with 70's using about 10gr. less powder.
 
Originally Posted By: xtrempredhntrCost- as much as you want to spend
Bullet velocity- fast
Range- way out there

Honestly, the cost is going to be determined on if you have an action for it already, what barrel you want, and the cost of labor for putting them together.
As for velocity have found some data online (not always the most reliable)
75gr-RL22/63gr=3665fps
85gr-RL22/61gr=3469fps
105ge-RL22/57gr=3224fps
That is with a 24in barrel 1-12" twist.
and for range...well that will be as far as you limit yourself too. I don't know how much help that is, but I was looking at the 6.5 Gibbs for a while, but decided that when I do build a long range gun I will go with the 6.5-06 Improved. Not quite as many steps in forming the brass.

Wow. What a bunch of completely useless info. If you don't have any experience with one, save the BS........
 
I guess nobody can ask for advise without making 2muchgun unhappy. I think from now on if I want to start a topic Im going to check with 2muchgun to see if it is ok to post my ? ..... I bet the posts numbers would be waaayyy down.
 
I think he is still sore from the other post, and is just going around looking for things to vent on...and I see his post was VERY helpful. Oh binnowing, the load data came from "Gibbs' cartridges and front ingnition loading technique" manual. But "technically" I found it on the internet...so, if nothing else it is a good reference to get an idea of the round.
 
I've played with a number of Gibbs cartridges namley the 25,7mm,35 and 240.They all are fast,some obtain the velocity that the gibbs manual say they will,others did not.Rocky Gibbs was a bit of a hotrodder,meaning use his data with extreme caution as it appears to be on the hot side.
I believe the least favorite of his line up was the .240.It can be a real pissy cartridge to play with,unexplained pressure spikes are somewhat common.I have .240 in a encore barrel,I max out way before I reach Rocky's load data.Dies are expensive,group g. They are very tough on throats,barrel life is less than the 243 ackley or 6-284.
If it was me,I would look at a 6-284,velocity is plain fast,lots of data,dies are common and barrel life well that depends on the nut behind the trigger. I would gladly share all the info I have on load data for the .240 if you decide to go that direction
R
 
Before you start investing on a Gibbs project I would recommend you Read Fred Zeglin's book, he devotes a section to Gibbs calibers.
 
Well i guess my buddy was right when he said this gun would do over 4000 fps but ya i think making the brass would be a s.o.b. to do but if a person loves that gun he'll do anything to make it shoot. i imagine that this gun is a lil pricy though
 
Wolf hunter what was some of your velocities and what kind of barrel lenth were u using...my friend is thinking of going with a 30 inch
 

got the encore barrel in a trade,it is a 26" 1-12 twist.
It's best accuracy load was with 75 grn bullets and 61.2 grns of IMR 7828 for 3443 fps.This was a max charge.

If velocity is where it's at for you,the 25 gibbs will push 75's at your 4000 fps with a 27 inch tube,

Fire forming was not a issue,10 grns unique and cormeal seemed to work well in my rifles.The case is NOT fully formed,the shoulders were slightly rounded.The 2nd firing would result in a perfect case.

You really need to read what Rocky Gibbs writes about the .240 then sit down till the feeling passes about owning one.
A 6-284 will do everything .240 gibbs will do and with less powder.When the inventer of the cartridge basically try's to discourage you from chambering one, as in his book,it is time for careful meditation
 
OK- My buddy has a 30 gibbs. Ive helped him make brass for shooting in it. Now, I DO NOT have a 6 mm AI, or a 6 mm-284 but what are some real world velocities out of these three cartridges?

Realistically to me, the gibbs seems like it would be great for a guy who likes to make lots of brass and shoot very little.

Seems like a lot of work to make something that might be duplicated by a cartidge with less forming work.
 
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I have a 35 Gibbs, so I will pass on my experience with fire forming of the brass.
There is a lot of extra time devoted to making brass for a Gibbs, and also expense as well.
One good thing about the 6mm compared to my 35, there is a whole lot more shoulder to work with..
Somehow, when forming brass in a Remington, I managed to pop a primer.. Let me just say this.. I prefer the Mauser action when it comes to wild cats, and escaping gasses...
 
The barrel that I have played with was in a encore,a bolt could be pushed a bit more perhaps.
I believe max listed load was 63 grns of 7828 for 3511 fps,there are no listed loads above 3665 fps in the Gibbs manual with any powder,data was with 24" tubes.
I have both 243 AI and a 6-284 and they are faster and way more effecient.I am playing with a Nesika model K action that is chambered in 6-284.It has a 30 inch tube and will push a 87 grn v-max to 3700 fps.
The .243 Ackley is on a Praire Gunworks action has a 31" tube,the barrel twist is 1-8 and will dust almost all makes of lighter bullets so data in that rifle is unknown,however it will spit 107 grn MK's out at 3400 fps quite comfortably.
Rocky Stresses over and over again about shooting the .240 with less than full powder charges or running less than 100% density is very dangerous in this cartridge. I have no experiance with the .240 in longer tubes just the encore.
Just my findings
 
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