View Full Version : winchester model 100

November 5, 2007, 12:42 AM
Well I have a model 100 in 243 and want to change it to 308 I have a factory barrel in 308 and I want to know if I have to change anything else so when I start this I dont get it done and head spaced then find out I should have also changed something else:confused:

James K
November 6, 2007, 02:42 PM
Since the gas port will already have been drilled for the .308, and there is no bolt work to do, and if the external barrel profiles are the same I can't see any problems. Just make sure you have the proper receiver wrench for that action. Note that if headspace is OK you are good. If it is short, you can ream the chamber (is the barrel new short chambered or is it a take-off?). But if it is a take-off and headspaces too long, you can't set the barrel back, you will have to play with bolts until you can get the headspace right.

My inclination would be to try the .308 barrel and if things work, OK. If not, then just swap the barrel back and try to trade for a 100 in .308.

BTW, make sure you use a regular barrel vise and receiver wrench; don't try to screw the barrel on or off using the gas cylinder housing for purchase.


November 6, 2007, 06:29 PM
While your are working on it, make sure the firing pin has been replaced. In case you don't know it, there was a recall on the Model 100 due to a firing pin that had a habit of breaking causing the rifle to go full auto in open bolt mode. I know a guy in Georgia that collects them. He said all you have to do is call Winchester and give the the serial number and they will tell you if they have replaced the pin for that particular model. If they haven't, they'll send you a new one (they even sent him some cash to have a gunsmith do it, but he said it was easy to replace it by himself).