Chamber OAL

[cory]

Okay. I'm a little confused here. Are you saying that's a problem? Which bullets would jam if you loaded them to 2.26" COL?

[biodsl]

I did a little test because those Amax are sitting pretty deep in the case. I used the book COL 2.245 and the max charge 31.2 gr of CFE...

My Hornady manual lists the max of CFE as 31.7. Just as a point of reference, I measured several cartridges from a box of factory Amax loads, lot #3152506. They varied from 2.249 to 2.253. This is longer than a box I check around a year ago. Those seems to run right at 2.240.

[Rickc]

Okay. I'm a little confused here. Are you saying that's a problem? Which bullets would jam if you loaded them to 2.26" COL?

Not a problem. Just information you need if you are seeking out your best accuracy with handloads.

Which bullets would jam if loaded to 2.26 COL? you really don't know if you don't measure it. These modern long slim bullets are much less likely than the older style round nose bullets. A good example is the Sierra game King.

Factory ammo should never be a problem but for the Handloader looking for accuracy it is a must

[Dogue]

This is old news, but Hornady 120's have to be loaded short. This isn't a "chamber length" issue though so that might be why the OP is confusing.

[JASmith]

Check the Grendel reloading handbooks for OAL's others have used.

You will see why Dogue is on the mark aboutt this being old news. Some of the old news involved a fair bit of spirited debate and sometimes a bit of baiting. Hence the seemingly odd responses -- we don't want to start those pointless debates again.

Nonetheless, the discussion, if carried in the spirit of curiosity and exploration, will help the rest of us gain more insight.

[Rickc]

It seems many on this thread missed my entire point

I just asked how many used an overall length gauge to measure the overall chamber length with the different bullets they used. I do because I want to know the max overall length I can use with the bullet I am loading. I use this information when I start seating depth test

If you notice from the information posted about what others found thone dimensions were all different. You have to use what you found your barrel to be. It is not in any book.

This might be over the heads of those who are not experienced handloaders. Didn’t mean to start.a pizzing contest.

[JASmith]

Our confusion comes from having been involved in a lot of conversations on this topic. More than ten percent of our threads touch on case length. When one includes ogive discussions and OAL we see that the topic is touched on at least a third of the time in the reloading forum.

That, coupled with repeated assertions that we either don't measure or don't know about the issue causes a bit of pushback.

Have you tried searching for case length discussions? That would have answered your question and might have helped shape your question and discussion.

[Rickc]

Oh are you saying that I got mixed up in the debate about all the different grendel throats?

I never even thought about that one

I think JP uses a Saami chamber but I really don't care. I just want to find the best bullet, powder and seating depth that works with this barrel.

Guess I must have touched a nerve unintentionally

[cory]

Generally a short throat is seen as a problem and has caused heated discussions due to others ignorance and nothing to do with your post.

Likely due to this your OP came off as a "somethings wrong, I need help" post, as opposed to an FYI post. It was as if you were speaking chinese and we were speaking korean.

[Rickc]

Well I do apologize for anything I might have said

Now I understand

The debate about the grendel throat can go on Ad nauseam. Just leave me out of it. My opinion is all barrels are different. The fun is finding what they like. The more information you have about that particular barrel the more likely you are to find that magic combination.

You can see the same debate on the. 223 throat and the 5.56 throat. That is really the only difference but for many they believe they are completely different cartridges. Both work and now there are all kinds of Hybrids

I don't know enough about the grendel yet to even give an opinion about the different throats but I do know Bill Alexander knows his stuff.

[JASmith]

... And we also have the ongoing PRVI brass and cartridge discussion.

[JASmith]

Regarding the 5.56 vs .223 throat discuusion, the danger is that one allows for a slightly longer length from base to land engagement. Further, the 5.56 spec allows for higher pressures.

The result of seating the bullet so it engages the lands is order 5,000 psi higher pressures. Combine that with the already hotter loads in the 5.56 and it is easy to see why some worry.

The compound throat of the Grendel is more forgiving but one still sees an increase of pressures when the lands are jammed. That means the max load for bullet seated into the lands will likely be less than one sees for, e. g., a .003" jump or light kiss.

[Rickc]

Regarding the 5.56 vs .223 throat discuusion, the danger is that one allows for a slightly longer length from base to land engagement. Further, the 5.56 spec allows for higher pressures.

The result of seating the bullet so it engages the lands is order 5,000 psi higher pressures. Combine that with the already hotter loads in the 5.56 and it is easy to see why some worry.

The compound throat of the Grendel is more forgiving but one still sees an increase of pressures when the lands are jammed. That means the max load for bullet seated into the lands will likely be less than one sees for, e. g., a .003" jump or light kiss.

This is a very good read on the subject. Pressures also rise dramatically as you move towards a compressed load

https://www.google.com/url?sa=t&source=web&rct=j&url=http://www.bergerbullets.com/wp-content/uploads/2013/03/COAL.pdf&ved=0ahUKEwj8-f-NhJDPAhVDQBQKHSSpAp4QFggbMAA&usg=AFQjCNH65RayeWwky2wc5ZJ6kOUoB9_HQg&sig2=ZJcAeiRe1d4Oy_dOHqZ_bg

[Rickc]

Regarding the 5.56 vs .223 throat discuusion, the danger is that one allows for a slightly longer length from base to land engagement. Further, the 5.56 spec allows for higher pressures.

The result of seating the bullet so it engages the lands is order 5,000 psi higher pressures. Combine that with the already hotter loads in the 5.56 and it is easy to see why some worry.

The compound throat of the Grendel is more forgiving but one still sees an increase of pressures when the lands are jammed. That means the max load for bullet seated into the lands will likely be less than one sees for, e. g., a .003" jump or light kiss.

Interesting read on the .223/5.56 debate

http://www.luckygunner.com/labs/5-56-vs-223/

[JASmith]

Thanks! That is a good read ... And he put in a huge amunt tof time to collect the source material and to write it up.

His pressure traces are remarkably clean, which means he either cherry picked or did an excellent job of controlling wire runs and preventing interference. The picture of his test setup suggests the latter.