Gibbs .240 reloading data.
G*nmedic said: Picked up a sweet Browning B78 in .240 Gibbs. Looking for some loading data. There was a couple of loads on the box it came with, but was hoping any other CGN members may have some more info? Looking for as much info as I can on this cool rifle. Wish I could post a pic. Take care de Gunmedic. :D
d*n belisle said: I shoot a 240 Gibbs built on a Win 70 with a 26" Ron Smith gain twist barrel. What's your twist and what bullets do you plan on using? - dan
G*nmedic said: I have not checked my twist, and I have not yet really thought of the type or grain of bullets I am planning using. I got some loaded ammunition with the gun, and plan to pull a bullet to weigh it. As for the powder, the prior owner used 4831. As I write this I can see his loads are from PO Ackleybook. More research, but hey, thats part of the fun of shooting.
G*nmedic said: Hi Dan, My twist is 1:11 in. I wanted to go with 75-85 grain bullets. Shot the gun today, grouped very well. I have not pulled a bullet yet to weigh it. Any ideas? Also looking for proper headstamp brass. Thanks de Gunmedic.
d*n belisle said: There isn't any properly marked brass available, unless you get someone to run you off some. It's strictly a wildcat. Grayback wildcats stateside will sell you formed brass, but it's made from other brass, so the headstamp will still be incorrect. 1-11 twist should work with most bullet weights, maybe not the 115 gr vld's, but certainly the 95 and 100 gr bullets, and lighter. I've been using RL22 in mine lately, but 4831 is a good powder for it as well. I would watch the Ackley data, some of it is quite hot. Forming brass is easy, you neck down a 30-06 or 25-06 case, to form a false shoulder in the neck. You may have to neck ream and turn, depends on the size of the neck in your chamber, measure your fired brass to give you an idea of where to start. The false shoulder should just barely allow you to close the bolt on the brass case in the rifle's chamber, with some pressure required to turn the bolt down. Then use starting data from your load list, and fire the rounds in your chamber. If they come out smokey and/or with split shoulders, increase the load. Make SURE that your neck measurements are right, and that there is enough clearance for the neck to expand to release the bullet, otherwise your pressures will be sky high. You should be able to get close to 3600-3700 fps with the 85-87 gr bullets in one of these, does amazing things to gophers and coyotes. I have more load datra at home, if you want it PM me. - dan