First time reloader- using OAL gauge help

[street-doctor]

So I'm reloading 30-06 using Nosler 180gr partitions and starting at 43grs of IMR 4064.

I used the OAL gauge and measured 3.972" 4 times with a comparator. Where do I go from here to get my OAL? I measured without the comparator and came up with 3.557". If I subtract 0.030" to get off the lands a little I still come up with 3.527" which is still outside the max OAL (by 0.187") recommended in the Nosler manual (3.340").

Where did I screw up?

 

[street-doctor]

So I'm reloading 30-06 using Nosler 180gr partitions and starting at 43grs of IMR 4064.

I used the OAL gauge and measured 3.972" 4 times with a comparator. Where do I go from here to get my OAL? I measured without the comparator and came up with 3.557". If I subtract 0.030" to get off the lands a little I still come up with 3.527" which is still outside the max OAL (by 0.187") recommended in the Nosler manual (3.340").

Where did I screw up?

The rifle is a remington 700 long range (26" heavy barrel) in 30-06

 

[street-doctor]

Some more measurements. Seated to an OACL of 3.380" there's 0.503" bullet inside the casing. They all cycle fine. Should I roll with this?

 

[Mikecr]

It's really difficult to even understand what you're doing.
I'm assuming you're trying to find seating for just touching of the lands, and then measuring this with something. OAL is simply cartridge base to bullet tip. You can measure this with calipers.

Nosler's recommended OAL has nothing to do with distance to lands with your particular gun.
Think about what you're doing and what you want to do.

 

[street-doctor]

It's really difficult to even understand what you're doing.
I'm assuming you're trying to find seating for just touching of the lands, and then measuring this with something. OAL is simply cartridge base to bullet tip. You can measure this with calipers.

Nosler's recommended OAL has nothing to do with distance to lands with your particular gun.
Think about what you're doing and what you want to do.

Sorry for the gibberish... my brain was working through it as I was typing I guess lol...

You're correct, I was trying to figure out the proper "COAL" based on being .020-.040" off the lands. This number was over the max recommendation in the Nosler guide. After doing a little more searching online it seems like some rifles can take a longer round than what SAAMI recommends. Either way, I loaded 20 rounds at 3.380" COAL. I will mess around with making them a bit longer in the future.

 

[AZShooter]

You don't need your comparator or even a caliper to figure out where to seat a bullet. As you will find out many rifles have magazines that are too short to allow a bullet to engage the rifling.

My approach is to seat a bullet out as far as possible to fit and feed from magazine. I then will polish the jacket material with fine steel wool and chamber the dummy round. After removal the jacket is carefully inspected for any marks made by the lands. It is a rare package that has the bullet into the rifling.

If you want to know how far the bullet is from the rifling then you can use your caliper with the comparator. Seat a bullet so it is extending out of the case quite a bit. Polish the jacket and close the bolt on it. It may require some camming action to get the bolt shut or it may even be too long. Adjust so you can get the bolt shut. Remove dummy round and inspect the jacket for marks. There will most likely be some large engraved marks from the lands. (Don't expect this with all chamberings as some have huge freebores, the bullet will fall out of the case before it could engage the rifling.) Once you have a seating depth that engraves the bullet gradually seat deeper checking the polished jacket till the marks are very small. At some point you can call that kissing the rifling.

Take the comparator and measure your two dummy rounds. The difference is the jump to the rifling.

Conversely if you ever want to seat a bullet so it is heavily engraved into the rifling as some BR guys do, just compare the kiss measurement vs the heavily engraved find the amount of engagement. My friend Bruce and I both experimented with VLDs .035" into the rifling with a couple of BR rifles.

Last week I helped a friend make a load for his 257 Roberts that is built on an old mauser. This rifle is a long action so it had enough room for the VLD to engage the rifling and feed from the magazine! In this situation I seated a bullet so it engaged the rifling and still fed. I kept polishing the jacket and seated a bit deeper till I had an engagement mark from the rifling that was perfectly square. I called it good and worked my way up in powder weights.

Hope this makes sense.

 

[BountyHunter]

That system works if no other way but if you can see any marks you are about .030 to. 050 still in the rifling. Back off a little more if you do not want to touch.

 

[AZShooter]

I hear you Bounty Hunter. I use some pretty high magnification to spot the engraving marks. I can get closer than .030" more like .002" or so. IMO this information is used as a reference you really don't need the exact amount.

I own a Hornady Lock-N-Load Overall Length Gage and even have a tap to make my own modified cases that Hornady doesn't offer but I rarely the system.

I was trying to help a new handloader deal with an issue in an easy to understand manner with as few tools as possible.