Bruce Baer (717) 349-4077
Bruce will not pickup the phone so leave a message and he will return or return your email.
408 has a problem with bullets. Ie only lost river at $1 each. Can only get about 15-20 shots before barrel coppers bad and accuracy is downhill.
Leonard Baity at Baity Custom gunworks (336) 667-8785 has built 4-8 of the 408s for Bill Shehane Tom Sarver (ohio BR 1k range owner) and others. Leonard is top 1k br shooter, 1k smith and on top 100 pistol smith guild member. Leonard has the reamers on hand and can make the custom dies. Leonard has done work with all the barrel mftrs of the 40 and there are issues with some on their barrels, so I would talk to him for sure.
I have watched Bill and Tom both shoot the 408 at the Ohio mile shoots and coppering is a big problem.
"Randy in VA" on this site is working with bullet mftrs for custom bullets for the 408. Contact him and see what is going on. Barnes made him a 1000 custom 408 bullets. ;Not sure what his test of those bullets showed.
Can consider a 338 Lapua Ack Improved. Good brass ($1 each) and 300 gr sierras are good if sorted by ogive. Will give 3000 fps with 34" barrel and 300 gr sierras.
neil jones will build custom dies for $275 for the 338 Lap Ack.
If you go above the 32" on barrels, you will need a 9" barrel block, use the split model. That will allow you to go out to 36" or maybe little more.