Advice on loading cast .223

[kb8yrw]

I just started casting for .223 and have a question for anyone with experience. First the boolit is a RCBS 55g SP GC sized to .226. Im using range lead water cooled with a BHN of 22 (using a Cabine Tree tester). The boolits are dropping .225-.226 and lubed with Carnauba Red and Hornady gas checks.

I'm using mixed brass and trimmed to 1.74" (using RCBS X-die for sizing). I'm loading using 23.5g of IMR 4895 and seated the boolit with a COA of 2.12. This load Chrony'ed at 2570 FPS average (10 shot) and had no leading in the barrel at all. I did not check for accuracy because I was initially more interested in leading and function plus I was waiting for my OAL gage and bullet comparitor to arrive. This leads me to my question.

I checked the OAL to the lands and it measures 2.24". At this length the case seats on the boolit below the lube groove.


http://dl.dropbox.com/u/19847411/web...2007.57.09.jpg

If I back the boolit up slightly to take it off the lands it puts the case mouth in the lube groove. My question is should I seat the boolit up to the driving band as I orginally did or expose the lube groove. I know I have to check for accurancy but it just seems that seating it to the driving band really backs the boolit off the lands and creates quit a jump. Anyone dealt with this before?

Thanks in advance!

[Larry Gibson]

What rifle?

Larry Gibson

[kb8yrw]

Sorry that would be helpful. I have two AR15's one is 16" and the other is 24". The 16" is a 1/9 and the 24" is a 1/8 twist. Both of the chambers measure identicle to the lands. The Chrony figure I stated was out of the 24" the average out of the 16" was about 150 FPS slower.

[madsenshooter]

I had an Eagan 169gr bullet that seated out like you've pictured. It was terribly accurate at 2000fps out of my Krag. My theory was that most of the lube, at ignition, was atomized and thrown down the bore ahead of the bullet. Not much time for it to do that before the bullet closed the bore though. Since you're below magazine length and have a load that is functioning, all you have to do now is find the velocity for accuracy. The closer to the lands the better. Least that's what my 6x45 prefers.

[Larry Gibson]

Sorry that would be helpful. I have two AR15's one is 16" and the other is 24". The 16" is a 1/9 and the 24" is a 1/8 twist. Both of the chambers measure identicle to the lands. The Chrony figure I stated was out of the 24" the average out of the 16" was about 150 FPS slower.

I'd leave them seated out if they fit in the mag and feed as pictured unless your shooting envirnment is very dirty where the lube would pick up dirt. I shoot lots of 225462's with lubed grooves hanging out in my 3 ARs, SSs and bolt guns.

Larry Gibson

[Gunnut 45/454]

KB8
Now shoot a group at 100 yards ! I want to see what kind of grouping your getting! I have to run mine alot slower as the groups went to hell at about 1950 ish fps! I'd keep it as close to the lans as possible IF your getting good accuracy!

[badluther]

I would be curious to see the 100 yd group as well (5-10 shots). I'm impressed your getting 2570 FPS. I am loading 62gr cast .223 bullets and max I am getting is a mean avg of 1750 FPS (20.25 gr of IMR 4895).

[Larry Gibson]

Note in the photo of the 225462 in my above post that there is lube in the 2 lube grooves and ahead of the GC. It shows a bit in the scraper groove but I usually do not put lube there. The two major grooves lubed and the bit above the GC are sufficient with Javelina (NRA 50/50) or 2500+ at 2300 fps out of my 12" twist 20" AR barrel (RL22 powder) for no leading after 200 rounds. Accuracy is on par with US M193 ammuntion in that rifle.

Larry Gibson

[GabbyM]

Your AR's have a 5.56mm NATO standard chamber with it's long free bore. As opposed to a 223 Rem SAMI chamber which would have less free bore.

[Larry Gibson]

Your AR's have a 5.56mm NATO standard chamber with it's long free bore. As opposed to a 223 Rem SAMI chamber which would have less free bore.

Will depend on when the .223 chamber was made. I have a Clymer .223 Rem reamer I got in '70 that has a throat pretty much the same as today's so called "5.56" chamber. My M700V made in '72 also had the longer throat. My Contender Carbine barrel and M70 XTR made in '81 have the shorter current SAAMI spec throats. My Savage Comp .223 match rifle made in '95 also has a long throat with the 9" twist for 69+ gr match bullet loads. Like the twist rate oin .223s the chambers also seem to vary widely.

Larry Gibson

[felix]

The boolit is adjusted back and forth to where it meets and/or engraves the lands in order to find the best ignition point for the load. Change anything and the vibes will change making the boolit release differently from the muzzle. For example, speeding up the powder/primer ignition characteristic requires a larger jump to the lands for the same results at the target. ... felix

[Gunnut 45/454]

Since the OP hasn't posted a target with his load I loaded up some at 23.5 gr and went out to see how they would group. The load consisted of the NOE 55gr lubed with Alox in PMC cases trimmed to 1.750" and 23.5 gr IMR4895. I didn't chrony these but I suspect they are very close to what the OP stated he got! I had three flyers in the group on the target that are marked- as I think I ginked the bullets when seating them. Other then those flyers not a bad group even though it was only 50 yards my old eyes were bugging today so I figured I better shoot at 50.

[kb8yrw]

I apologize for not following up with this but the weather has been **** and with the holidays coming up we have been putting some long hours in. When I get off work it is dark. I have loaded up several rounds with varying lengths to test. I might try and get out tomorrow if the range is open and it isn't raining. My son and grandkids are home from the army it would be fun to go to the range with him. I will post the results if I get out.

[JIMinPHX]

These are 225415HPs in a .223. They worked well for me in a single shot. There was almost no part of the boolit inside the case neck. All the lube was external. I wouldn't try these in an autoloader only because I would be worried about the slug getting knocked out of the brass.

[Gunnut 45/454]

KB8
Well I went out and chronied the load an your guess on the speed was very close. I averaged 2382 FPS in my 16" carbine. Accuracy at 100 yards! Pitifull! As I suspected. Now this might be due to my alloy but I suspect it's more to the fact they are just going to fast. I've had good luck with this alloy in my '06 up to 2250 FPS out of my Rem 7400- need to go that fast just to get full function accuracy is about 2" at 100 yards! So I'm loading the next batch at 22 gr IMR 4895 to get down to around 2200 fps and see how the groups look at 100 yards ! I suspect they will tighen up alot.

[kb8yrw]

I still have not got out to shoot. The range was closed due to hunting season..........I want to hunt paper!!!!! I could shoot in my back yard but I do not like to do that unless I'm shooting handguns. Maybe this weekend.

Gunnut - Very interesting, I never really thought about slowing them down. I suppose with the bullet extended out of the case that is going to slow them down a bit. I may have to load up a few dozen with a lighter powder load duplicating the COA of the ones I have ready for testing.

[Gunnut 45/454]

KB8
I load mine to and COAL of 2.070" with this Lyman bullet cause If I load them longer the jam. At this COAL they feed like a champ in both of my 5.56mm. If the weather is decent tomorrow I'll get out an shoot them. Now at 23.5gr they are useable at around 50 yards but I demand atleast decent grouping at 100 yards better yet to 200 yards! Now this same bullet at my usual load of 18.7 gr groups about 6" at 200 yards.

Well I got out and shot the 22gr load Avg vel 2135fps big improvement in group but I was shooting chrony so the group could be better. I loaded up the next lot with 21.7gr and it will be shot for group at 100 yards and not chronied they should be around 2075 ish.

[Wilkie]

Great post guys! I have been using cb in my AK for a while now. Have been curious to try it in my AR. I want to use H4895. I have an RCBS mold coming. I'm worried about the light bullet and light loads not cycling the gun properly. Looking forward to some new plinking fun!

[Gunnut 45/454]

Wilkie
Well got down to 21gr load with IMR 4895 at 100 yards groups are still about 5-6" not good! With my normal load of 18.7 gr IMR 4895 I get about 2-3" groups or less those run about 1890 ish fps with full function in my AR's. I think the next time I'm going to try them in my PSA 1:7" twist as it has a better trigger then my 1:9" or maybe I'll just swap the lowers around. Going to be awhile before I do this as the weather is bitterly cold right now.

[Moonie]

16gr of H4895 cycles our mid length gas upper with 55-60gr boolits.