6mmBR barrel questions

[BoilerUP]

For anybody with a McGowen, Shilen, or (especially) CBI 6mmBR barrel:

How long are the throats? Can you easily use the 107gr SMK/105 A-Max without it being seated overly deep in the case?

Thanks...

[bootsmcguire]

I have a CBI and I can't speak for the MK or the A-Max since I have not picked any up yet (on my to-do list). I did load some 100gr Sierra Spitzers and had an OAL of 2.250 and I was not jamming in the lands. Best measurement I got was that length was about .050 off the lands.

Don't know if that helps or not but there it is.

[yorketransport]

I have a CBI barrel in 6br and you can hang the 105gr A Max way out there. I'll get a measurement when I get home.

Andrew

[yorketransport]

My 6br loads with the 105gr A-Max have an OAL of 2.295" seated right at the lands. Hope this helps.

Andrew

[LouB]

In my Shilen 6mmBR with SRA HPBT 107gr bullets it is 2.402 OAL to the lands. Hope that helps.

[Cover Dog]

BoilerUP.....I posted this about 3 months ago, this may help you. This is for a CBI 6mmBR 8T barrel.

If anyone sees something that doesn't seem right, jump in and let me know.

Using a Hornady Lock-n-Load OAL gauge I got these results.

Berger 105VLD 2.427"
Sierra 107 2.390"
A-Max 105 2.324"
A-max 87 2.262"
A-Max 75 2.203"

I am using NEW paper box Lapua brass that the OAL is 1.556". Using the above measurements this would mean that:

A-Max 105 had .456" in the case (bullet lenght 1.224" )
Sierra 107 had .401" in the case (bullet lenght 1.235")
Berger 105VLD had .363" in the case (bullet lenght 1.234")
A-Max 87 had .334" in the case (bullet lenght 1.040")
A-Max 75 had .290 in the case (bullet lenght .937")

Using a Sinclair chamber length gauge it measured 1.578" and the measurement to the lands with a Berger 105VLD was 1.668"
To the lands= 1.668"
Chamber lenght= 1.578"
Freebore = .090

Since I took the above measurement I have talked to Jim Briggs and he said the free bore according to the reamer CBI is using should measure at .093"

Old paper box Lapua brass has the shoulder .003" farther forward then the new Blue box I have. Measurement to shoulder 1.068" old brass / 1.065" new brass. Which leaves the new Blue box brass .003 shorter in OAL then the old brass. This was measured in a Hornady head space gauge using Sinclair SS inserts. OAL old 1.556 OAL new Blue box .1553

[MDM]

I've got a McGowen. I shoot the 105 amax .012 off the lands for a COL of 2.350. When I shot the 107 smk the COL was about 2.410. I've got 700 rounds thru it, slow fire for the most part, with 0 throat erosion. Shot it as some steel last weekend at 1100yds and it does quite well with the 105 amax.