I had a custom rifle built in 22-250. Was built with a 7.7 contour broughton 8 twist barrel. GA precision left it at 27 inches long at my request. I was real happy 'cause I was able to get >3000fps with the 75gr. A-Max(one of my goals). Now the problem...The gun is so heavy I dont like to carry it to the range let alone on a varmint hunt. Also not balanced at all with all the weight up front. I'm thinking about having it shortened to 20-22 inches. If my g'smith has to remove the barrel to do this should I rechamber to the 40 degree ackley? Do you think I might be able to achieve the same velocity?

You might be surprised at the velocity you can get out of a modest length barrel chambered in 22-250 or the AI version.

Basically the AI version gives you the 220 Swift in a better package. We are only talking 37 to 38-ish grains of powder being burned with 75gr bullets. it doesn't take a mile of barrel to get the most out of that.

If you lost more than 25 fps per inch of barrel, with the original chambering, I'd be shocked. 100 to 125fps isn't much when you're around 3000 fps with a bullet sporting a .435 BC.

Heck, if you're really nervous about going that short, go 24" first and see what you think. You can always go shorter, but it is an expensive proposition to add inches.

You might also look into having the barrel fluted to reduce the weight. Fluting shouldn't cost more than $125. Some posters will probably tell you that fluting after the barrel has been fitted, chambered and crowned will adversly affect accuracy but Dave Sullivan;
Westwind Rifles
640 Briggs St.
P.O. Box 261
Erie CO 80516
Phone: 303-828-3823
has done many after fitting with no decrease in accuracy, including one for a friend who was very pleased with the results.
Phone: 303-828-3823