I bought this NEW remington 700. I wanted a 308, but it only comes in a faster twist in the varmit model. I settled on the 22-250.
Went home, tried this and that. Shooting jacketed boolits, 100 or so jacketed for the brass and to smooz out the barrel. I was trying a few cast loads having great luck. I was using IMR 4227 data for WW 296. Things were good. Jacketed performace was nothing fantastic, but cast was fine for staters. I used 35 grains of 748 for my jacketed stuff and it worked well. SOMEHOW I put 35 grains of 296 in some jacketed loads. The containers look the same and I didn't realize it until it was tooo late. I fired one of those 40 grain factory loads over my crony to see if it really reached 4,000 fps. 3898. Good enugh. I put in what I thought was another of the same. I pulled the trigger and got sprayed in the face with powder. I am blessed with poor vision, so I always wear glasses. Nothing serious to me, but the gun was another story. I looked at he chrony, it said 4195 fps. This was a 55 grain jacketed boolit. The bolt wouldn't open. I packed up my stuff, and went home happy I wasn't hurt. I put the gun on the bench, took a block of wood and a hammer to see if I could open the bolt. Tap...tap...tap... off came the bolt handle. OH SH*t. I called the ammo manufactor, told them what happened ( I thought it was the factory ammo). They sent me a shipping label pre paid. They wanted to see the gun and what was left of the ammo. I also called remington to see what they would do. They did the same thing, sent me a pre paid UPS shipping label. I sent the gun off to remington. Aftere it was gone, I realized that what I had done. I keep good records and looked at my box of ammo. 15 factory loads, 13 reloads. There were 14 factory loads and 12 reloads left in the box I used that day. I had picked up one of my handloads when the gun went ka boom. I wrote to Remington and told them what I had done. This was just before christmass. Remington fixed the gun....new barrel, bolt and all the parts in the bolt. I ended up getting the stock and reciever back from the original gun. NO CHARGE "to promote good will". One happy camper.
I have been loading since 1987 and this is the first time this has happened. I have a reminder on the stock where the action has a vent in the side of the chamber and a burn mark on the stock from the over pressure. I looked up the max load for IMR 4227, its 21 grains. I loaded 35 of WW296. Good gun, good company, Lucky shooter.
Now I keep ONE can of powder on the bench. I READ the label before I load and double check my loads. I pulled every load I had for that gun and trashed the powder. 296 looks exactly like 748. No problems since, 500 or so rounds later, but I am more careful.