30 Gibbs and 165 to 178 grain bullets

[TAWS]

I'm sure this has been covered before but I have a new rifle in a30 Gibbs cal. Right now I am "trying" to shoot 165 Nosler's & 168 comb. Tech. Bullets. Rifle does not like 64 gr. of h4831 or re22 touching the l&g's. Flattened primers big time & stretched & cracked brass (Quality Cartridge) and came from them as 30 Gibbs head-stamped and all. I am looking for 3100 to 3160 velocity. Suggestions please. I have backed off the L&G's about 20 thou. and flattened primers are looking better. Using fed 215 mag primers.

 

[Jud96]

Well first off I would work up to pressure before jumping to a max load before you continue damaging your brass. You need to first find a powder charge that your rifle likes and gives low velocity spreads and is in a node. Then work on seating depth. Start .020 off the lands and work back in .005 increments shooting 3 shot groups until you find a seating depth node. You want to have at least 2 or 3 groups in a row that shoot to the same point of impact and shoot acceptable groups.

 

[TAWS]

Well first off I would work up to pressure before jumping to a max load before you continue damaging your brass. You need to first find a powder charge that your rifle likes and gives low velocity spreads and is in a node. Then work on seating depth. Start .020 off the lands and work back in .005 increments shooting 3 shot groups until you find a seating depth node. You want to have at least 2 or 3 groups in a row that shoot to the same point of impact and shoot acceptable groups.

Yes and worked up to that powder charge and 61 and 62 were ok but the seating depth according to the blackened bullet had had 3 marks on it. I have backed off 20 thousand from those marks. Now we will have to shoot it and see how it does.

 

[FEENIX]

I'm sure this has been covered before but I have a new rifle in a30 Gibbs cal. Right now I am "trying" to shoot 165 Nosler's & 168 comb. Tech. Bullets. Rifle does not like 64 gr. of h4831 or re22 touching the l&g's. Flattened primers big time & stretched & cracked brass (Quality Cartridge) and came from them as 30 Gibbs head-stamped and all. I am looking for 3100 to 3160 velocity. Suggestions please. I have backed off the L&G's about 20 thou. and flattened primers are looking better. Using fed 215 mag primers.

I am not sure about R22, but 64 H4831 on a 165 or 168 should be fine. I have loaded 61 H4831SC with 190 Berger with plenty of room to spare without any issues. IIWY, I would double-check the powder charges. Recalibrate and compare with a know good powder scale. Having a cracked brass indicates high pressure and possibly be dangerous.

 

[TAWS]

Could it also be due to headspace as I can insert a fired case in the chamber, close the bolt as if there is nothing in the chamber, then open the bolt and the cartridge is still in the chamber. It comes out very easy, as I can just bump the stock and it falls out.

 

[can1010]

with the Gibbs being a true wildcat it is almost impossible for a brass manufacture to make brass to fit all of them. after reading the first post headspace problem is a real good possibility and the biggest cause of all your problems. expand your necks up to 338 or 35 and then back down to 30 creating a false shoulder to fit brass tight in chamber before firing.
@FEENIX has good pictures of his using 35 Whalen brass with false shoulders for fireforming.
false shoulders and brass annealing are pretty common practice when moving so much brass around in wildcats.