Browning 7mm Chamber Length - Short?

Wyoredman · September 7, 2012, 09:22 AM

I posted yeserday about some loads for a 7mm RM (Win 70) that I recently aquired. Last night, I was talking with a friend about the 7mm and he stated he has one (a Browning A-Bolt) but has never shot reloads from it. We got to talking a bit more and he decided to go home and get his rifle.

When he brought his rifle back, we tried to chamber some of the rounds I had made for my rifle and they were obviosly way to long. So we stuck a bullet in the lands and held it there with a pencil, ran my cleaning rod down the barrel, marked it then removed the bullet, replaced the bolt and marked the rod again.

The measurement came to 3.110"! The chamber on my Win 70 was measured the same way and is 3.292". The two rifles are 0.182" different, that is more than 1/8th of an inch".

Has anyone every found a rifle chamber to be this much smaller than SAAMI spec?

PA-Joe · September 7, 2012, 03:46 PM

Lots of variaton in throat lengths that is way you have to reload for each individual rifle. Or reload for the shortest.

jdillon · September 8, 2012, 09:39 PM

Between manufacturers there will differences in the amount of free bore. My friends .270 Browning A-Bolt is similar to what you described. Rounds that chamber easily in a 700 are tight in the Browning.

September 7, 2012, 09:22 AM	#1
Wyoredman Senior Member Join Date: September 6, 2011 Location: Wyoming Posts: 1,350	Browning 7mm Chamber Length - Short? I posted yeserday about some loads for a 7mm RM (Win 70) that I recently aquired. Last night, I was talking with a friend about the 7mm and he stated he has one (a Browning A-Bolt) but has never shot reloads from it. We got to talking a bit more and he decided to go home and get his rifle. When he brought his rifle back, we tried to chamber some of the rounds I had made for my rifle and they were obviosly way to long. So we stuck a bullet in the lands and held it there with a pencil, ran my cleaning rod down the barrel, marked it then removed the bullet, replaced the bolt and marked the rod again. The measurement came to 3.110"! The chamber on my Win 70 was measured the same way and is 3.292". The two rifles are 0.182" different, that is more than 1/8th of an inch". Has anyone every found a rifle chamber to be this much smaller than SAAMI spec? __________________ Go Pokes! Go Rams! Last edited by Wyoredman; September 7, 2012 at 09:41 AM.

September 8, 2012, 09:39 PM	#3
jdillon Senior Member Join Date: October 7, 2011 Location: Southern NM Posts: 141	Between manufacturers there will differences in the amount of free bore. My friends .270 Browning A-Bolt is similar to what you described. Rounds that chamber easily in a 700 are tight in the Browning. __________________ "Emergencies have always been the pretext on which the safeguards of individual liberty have been eroded" - F.A. Hayek

September 7, 2012, 03:46 PM	#2
PA-Joe Senior Member Join Date: June 9, 2010 Location: NEPA Posts: 909	Lots of variaton in throat lengths that is way you have to reload for each individual rifle. Or reload for the shortest.