FN49 Barrel Swap - Complete

[spencerhut]

Got a FN49 as a gift from the wife. It had badly worn barrel and the chamber was so loose the brass was all being destroyed. Found a new/surplus barrel from SARCO. Ordered headspace gauges from Brownells and started looking for a receiver wrench. Never could find one so I ended up making my own from a 1/4" x 3" flat bar. I already had a Farrel barrel vice. Soaked the receiver threads in Kroil and heated it every day for a week putting more and more pressure on it until it finally broke loose.
The new barrel was a bit different than the old one, slightly thicker flange. I had to face the receiver a tiny bit with some 180grit sanding cloth to get it to clock properly.
When I checked headspace the locking block need to be taken down from .308 to .306 to let the bolt fall gently into battery.
Once it was all back together I test fired it and accuracy was good and the brass was coming out unharmed, other than a dent or two.
Success!

Information

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[spencerhut]

Loaded up some ammo for the new barrel today. Being a frugal fellow I worked up a load utilizing some free'ish Remington 185gr Core-Lokt bullets I had lying around. Ended up at 46.5gr of IMR 4064 lit off by CCI large rifle primers contained in some once fired Remington cases. Bullets were seated 2.97" ~ to middle of the cannelure
The load printed a bit high for my sights, but that is okay. I'll order some proper bullets and adjust the sights once the barrel is good and broken in.

For future reference the load I worked up went over my Labradar chronograph at 2475 FPS with an Extreme Spread of 22 FPS and a Standard Deviation of 11 FPS. The gas system on my gun was fully open and function was 100% with cases ejecting briskly from 2 o'clock to 6 o'clock.
Loads were prepared on a RCBS Pro2000 press with Lee dies. A crimp was applied with the Lee Factory Crimp Die.

[browningautorifle]

Sounds like it's fine...all worked out.