.243 SAAMI factory throat dimensions

[wildcat284]

Hey guys,

Did a search for this, just in case it's been answered. Does anyone have the SAAMI specs for a factory .243 Winchester throat diameter?,My rifle is a Sako AII). Some of the necks of my brass look like they need to be turned down as they are starting to look a little thick,have not experienced any higher than normal pressure signs, and I can still get a bullet in a fired case neck no problems), but I just want to be careful. First time loading a .243 and I have heard nightmare stories from other .243 shooters about necks getting so thick the pressure goes through the roof.

My necks are currently .274 dia with a bullet loaded.

Regards,

Michael.

 

[Cheechako]

Michael

I think you mean neck diameter, not throat. I don't have drawings in front of me but I believe min chamber dia is .277 and max cartridge is .276. If you are able to slide a bullet into the neck of a fired, not sized case, you are OK. That is always a good test to do on fired cases whether it's a factory or a custom chamber.

Ray

 

[Lane]

Dimensions and tolerances that you can use as a reference!,reference),inches) .243 Winchester case neck .276 /.268. Bullet .2430 / .2400. Bore .237 /.239. Groove .243 /.245. Chamber / neck .277 /.279 Very important dimension / tolerance in my view is the case web. .4703/.4623. along with the dimension / tolerance of the case before the case shoulder! .4553 /.4473. Your fire-formed, master case) will tell you a lot about your particular chamber and what you,can) and,can not do) with your dies. Your ammunition loaded .274 @ neck? Your fire formed case neck before being run through your dies? After your case neck is run through your dies? before and after bullet seating? I'm assuming your request for information is with case and case neck your chambers throat or lead is unique and particular to your chamber when reamed. Personal opinion & best wishes Michael! Lane