A buddy dropped off a new Cooper .223 his new gopher/PD rifle.

I've got a mess of Federal and GI cases. Several lbs of Viht N-130, RP 6 1/2 primers and 50,52 and 55 gr Calhoon slugs. And a lesser amount of Nosler poly tipped slugs too.

NOT wanting to reinvent the wheel,can anyone save me some load development time for this Cooper??

Whats been a good OAL? How far off the lands?

NOT looking for THE highest velocity load, simply minute of ground hog.

FN in MT

pick a load -= most anything in 2223 works well & i haven't seen a cooper that was anything but close to perfect yet

I had problems with 6 1/2 Rem primers blowing in 223 loads and REMINGTON said not to use them in 223...they are for Hornet and 30carbine ect.....they said most new manuals noted this....also I had a Cooper in 223 that had a chamber so long/oversized that the primers backed out when they didn't blow....sent back to Cooper and then it wouldn't chamber factory ammo for the extractor being so misfitted......this was several years ago and and a bad rimfire cooper ago...hth..good luck and good shooting-loading!!

I must agree that the primers need to be changed out to Fed 205M, or the Remington 7 1/2's, or CCi small rifle benchrest. That said the V V 130 is a great powder for the .223. These target are 100 Meter groups from a 16" Armalite AR15 with a 1 in 9 twist. You decide if that would be adequate, scope a Leupold 6x42 duplex.


The first target was shot with V V 130 and Hornady 53 HP's and from the magazine. The lower left five then a sight adjustment, and the extreme two uper left, a sight adjustment and the tight three upper left. A click left and the upper five right, aclick back to te right and two down... the last five lower right.



This second target was to try AA 1680 and the light weight bullets... action functioned perfectly except the bolt did not stay back after last round... pressures were up there however, so this is maximum for me. These are all ten shot groups. The 45 grain moly Bergers were beyond my expectations! First round fouler got away, and I was loath to fire the last five as to ruin the group... they didn't

My brother and I both have cooper 223's. Both really like 25-25.5 grains of H335 with a 50 grain bullet. That is the load they test them with at the factory.

Rocketman,

Did cooper give You an OAL that they use in the .223?

I'm stuck with the Viht powder as thats what the rifle owner gave me. I'd like to use up HIS components, not MINE. Bad enough I have to switch out the useless 6 1/2 primers with my own.

FN

FN in MT

my savage likes 24.0 grains of aa2460 with sierra 53 grain hp match, 24.0 aa2015 with a 50 grain nosler balistic tip and 24.5 aa2230 with a 50 grain nosler balistic tip. with all 3 loads i am near the rifling( not touching) all 3 loads shoot at .45 of an inch using winchester small rifle primers. these loads i am using are about middel of the road for accurate powders and i used the load data from accurates load book.
i have never used calhoon slugs. berger bulletts shoot well too.
try a few loads of what you have with the n-130 to see if the cooper will shoot it well enough, then go from there. its a 50/50 chance and worth trying.

For the Cooper model 21 in .223 caliber I have used a 50 grain Sierra Blitz King bullet seated to an OAL of 2.295. This is for a "standard" barrel with a 1 in 14 twist.

For my rifle, this load is approximately .030" off the lands. I have also tested this load with an OAL of 2.310 and 2.315 (.020 and .015 off the lands) with good results.

-----Corrected measurements 2-5-08-----

*** IMPORTANT: This OAL exceeds the maximum recommended OAL for .223REM (I think this is 2.250). You should exceed this maximum recommendation only if you are sure that your specific rifle will chamber this load safely, meaning that the bullet is not seated into the lands. It is likely that Cooper has used different chamber reamers at different times. This means that the chambers of some Cooper .223's may have different distances to the lands. You should load rounds that exceed the recommended OAL only if you fully understand what you are doing.

my vit avoy 2002 loading guide says....2.244 ..OAL for their 50 tnt 52 hpbt sierra 55 fmj 60 hp andhpbt sierra.
50 gr start with v-v n130 23.0....to 24.9 max.
52 gr. '' '' ''- '' ''=21.5.......''24.0 ''
55 fmj '' '' '' '' ''=22.1.....24.1 max
test barrel 25 inch 1-12 twist small primer,laupa case.. hope this helped..ps use the federal brass (caution) load safe n regards