.222 rem mag C.O.L. problem

[bluekouki86]

I am loading a batch of .222 rem mag for a Remington 700. I'm using hornady 52 gr bthp and aa2015. The 8th edition hornady manual says C.O.L. max is 2.280" for this caliber, but gives a C.O.L. of 2.325" for this bullet. What gives?

I loaded a dummy and chambered it and came up with a 2.300" and the bullet in the rifling. Should I stick to the 2.280"? Am I using a bullet that isn't compatible with this application? Like I said, I'm using published data so this shouldn't be terribly difficult. Any thoughts?

 

[bluekouki86]

I forgot to add I am worried about over pressure seating the bullet further and keeping the published charge (starting at the 23.2 gr accurate 2015 data).

 

[Walkalong]

What OAL is the data worked up for? If it is "gives a C.O.L. of 2.325" for this bullet", that's weird. Typo?

My .222 Mag likes .040 off the lands, and that is pretty long. Well over the max OAL and a single feed only thing.

If you are getting to the rifling at 2.300, your throat is shorter than mine.

My .222 Mag liked AA 2015.

 

[bluekouki86]

The powder data comes from Accurate's website for a Nosler 52 gr bthp at 2.295". Its the closest I could find for the powder. The 8th edition hornady does not list 2015.

I double and triple checked the C.O.L. numbers and my eyes are not deceiving me. In fact ALL of their C.O.L. data for every bullet is longer than 2.280".

Would I be ok .020" off the lands seated to 2.280" at the charge I'm at, or should I go below max length and reduce the charge further? This is a brand new load so I'm working from scratch and would like to stay closer to the bottom range.

 

[243winxb]

222 Remington Magnum

SAAMI shows a minimum of 2.220" So your ok using a starting load at a shorter COL. http://www.saami.org/PubResources/CC_Drawings/Rifle/222%20Remington%20Magnum.pdf You may have a custom barrel or rechambered barrel with a shorter leade/throat, all ok when working up from a starting load.

 

[243winxb]

222 REMINGTON MAGNUM
Barrel: 24” ¦ Twist: 1-12” ¦ Primer: WIN WSR ¦ Bullet Diameter: 0.224”
Case: REM ¦ Max Case Length: 1.850” ¦ Trim Length: 1.840”
ACCURATE 2015
40 NOSLER B-TIP 23.9 3,194 26.5 3,630 48,500 2.345
45 NOSLER HORNET 24.3 3,098 27.0 3,521 47,200 2.220
50 SPEER TNT HP 23.9 2,991 26.5 3,399 49,100 2.320
52 NOSLER HPBT-CC 23.2 2,942 25.8 3,343 49,900 2.295
55 NOSLER B-TIP 23.0 2,833 25.5 3,219 47,200 2.310
60 NOSLER PART 22.1 2,716 24.5 3,086 48,800 2.330
63 SIERRA SMP 22.3 2,700 24.8 3,068 49,800 2.280 The Nosler 55 gr BT is a long bullet requiring a lot of its shank into the case at the above COL . Not a problem even at a COL of 2.310" as posted here. The pressures listed are low compared to SAAMI standard maximum of 55,000 PSI http://www.saami.org/specifications_and_information/specifications/Velocity_Pressure_CfR.pdf

 

[steve4102]

It's important to understand the the SAAMI COAL/OAL minimum and maximum are for Ammunition manufacturers. This standard is set so all Factory ammo will fit in all Factory rifles.

These SAAMI specs have little of nothing to do with the handloader. The handloader is free to adjust his/her OAL/COAL to whatever works best for them.

The OAL/COAL listed in the manual is equally unimportant for the same reason. These manual OAL/COAL are there to show the handloader what OAL was used during testing, it is not a recommendation and it is certainly not a requirement.

Some manuals don't even list the OAL/COAL tested it is that Unimportant.

 

[Walkalong]

My Sako is a 1 in 14 twist and tends not to shoot anything over 55 Gr very accurately.

a custom barrel or rechambered barrel with a shorter leade/throat

Would be my guess.

Yes, if you start at .020 off the lands and work up you'll be fine.

The .222 Mag has 5% more case capacity than the .223, but is loaded to lower pressures, so factory ammo tends to run the same velocities. At least Remingtons used to according to their ballistic handouts. So, .223 loads can be a very good guide if you are careful, especially if you have a rifle that you feel can handle .223 like pressures, which should be any modern .222 Mag. You are on your own if you try this of course. .223 data can't be used as .222 Mag load data, but it can be very useful as help for loading .222 Mag where data is not available.

 

[243winxb]

Short throat/leades raise pressure, just as seating into the lands ups pressure about 10,000 psi so Quickload users say. The OP should be concerned about pressure. I would load 3 with a COL just off the rifling using the starting load, to be safe.

 

[bluekouki86]

All great info. Thanks for the replys.

So with the info Steve has provided, I should just seat to what works best with my chamber? I know that 2.300" is in the lands, so I will be ok at 2.280" and can work my load up from there?

I know this is a factory barrel. Its got all the correct markings, and has .222 rem mag stamped in it. I can't rule out modification though. I wonder why the throat is so shallow in a factory rifle.

 

[243winxb]

[/URL][/IMG]2.280" is ok. Has to fit the magazine also and enough bullet shank in the case neck. I like to start here if possible.