measurements from bigbear's grendel

[bigbear_98]

I posted this elsewhere, but decided it wasn't the right place. here you go.

http://accurateshooter.net/Blog/grendelsaami03.png

So according to this, If your oal is longer than 2.250 when using a drop guage you should be good correct?

I measured using 10 seperate bullets from the same box in my Krieger barrel just going overall length (tip to base as I haven't gotten my Ogive tool yet) and I got from 2.257-2.263 with hornady 123 sst. In one box of factory loaded sst I measured 2.246 max. What is everyone else that doesn't have a Satern barrel getting?

I'll try it with 123gr Amaxs when I get home.

ETA: DROP GAUGE IS NOT THE CORRECT TERM> Sorry, It is a Hornady LNL OAL gauge.

http://www.6mmbr.com/catalog/item/1433308/977259.htm

[bigbear_98]

Information on amax.

Amax oal
2.270
2.256
2.265
2.260
2.250

.02 variation

Amax projectile length
1.237
1.239
1.241
1.236
1.238

.005 variation

I'm not sure what to think of that. Does the ogive of these bullets vary that much? I'm guessing I'll know more when sinclair sends my 6.5 comparator insert.
Thoughts?

[bigbear_98]

I just had an epiphany and went to measure my fired brass from base to shoulder. It read as follows.

1.1385
1.137
1.138
1.139
1.1365
1.137
1.1375
1.1375

I then measured the Hornady modified brass that is used on my oal gauge.

1.128

All of my OAL measurements taken with this device are .01 short of actual chamber measurements.

So if my amax reads, 2.250 with the hornady oal gauge, then the actual chamber measurements are 2.260 correct?

Does everyone else see the information the same as me?

Now don't get me wrong, the factory hornady oal of 2.247 (max) that I pulled of the SSTs is shooting real well out of my rifle, so I don't think I will change that. With all this talk about short chambers and throats, I am just wanting information on my rifle.

[customcutter]

I'm still trying to figure out what a "drop gauge" is? Only thing I found on a google search was a die, that looked like it could be used as a "substitute" chamber to check ammunition?

[bigbear_98]

SAAMI spec drawing attached

http://www.saami.org/PubResources/CC_Dra...rendel.pdf

[bigbear_98]

I'm still trying to figure out what a "drop gauge" is? Only thing I found on a google search was a die, that looked like it could be used as a "substitute" chamber to check ammunition?

Sorry, It is a Hornady LNL OAL gauge.

http://www.6mmbr.com/catalog/item/1433308/977259.htm

[customcutter]

BB, thanks that makes sense. I was trying to figure out how you were using this???

http://www.google.com/imgres?imgurl=http...CC8Q9QEwAw

[bigbear_98]

BB, thanks that makes sense. I was trying to figure out how you were using this???

http://www.google.com/imgres?imgurl=http...CC8Q9QEwAw

Heh, I do have one of those, but I haven't used it yet. I keep trying to figure out how big of a hammer I will need to get it in the chamber.... ;-)

[bigbear_98]

Here are some Pics of my DIRTY chamber. Those that know, look at the last picture and make sure I labeled that correctly. I based this info off the SAAMI specs I posted earlier.

[bigbear_98]

I am posting this to ask questions and verify that I am understanding correctly. Does anyone have a "yes you're right" or "no you're and idiot" to give me?

[woohoo]

I am posting this to ask questions and verify that I am understanding correctly. Does anyone have a "yes you're right" or "no you're and idiot" to give me?

Yes, you are correct except with the Grendel there is no "freebore" that is the first part of the compound throat where the lands get taller at a 1/2 degree slope.
Only comment I have is the lands look like a pretty abrupt start.

[SHORT-N-SASSY]

. . . Only comment I have is the lands look like a pretty abrupt start.

That was my thought, also.

[bigbear_98]

That was my thought, also.

What are they supposed to look like?

[woohoo]

What are they supposed to look like?

A gradual slope maybe 1/8" long.
I'll try to take a photo of a 264LBC through the bore scope when I have some time, maybe later today.

[bigbear_98]

A gradual slope maybe 1/8" long.
I'll try to take a photo of a 264LBC through the bore scope when I have some time, maybe later today.

I think it may be deceiving. If you look at the rest of the chamber, neck length for example, it also looks very short. I took some pics of my WOA 223 wylde chamber for comparision. I wish I had a bore scope. I would like to see some pics of that!

[bigbear_98]

Pics of my 308

[woohoo]

You may be right, could be shadows.

[bigbear_98]

You may be right, could be shadows.

I would still love to see a bore scope picture