Range Report: Winchester 5.56mm 64 grain RA556B

[Molon]

The mean radius part should be stickied.

A-PRIMER-ON-THE-MEAN-RADIUS




Molon-Reference-Links



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[Glockman1968]

A-PRIMER-ON-THE-MEAN-RADIUS




Molon-Reference-Links



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As an aside, have you had ocassion to shoot the Nosler Defense .223 load? Be interesting to see the variables there.

Molon...making the complicated understandable. Thank you for your time and expertise.

Now I've got it in my head that I need a Noveske N4 Light barrel lol...

[DRT]

What B.C. were you assuming for your claim that the projectile would reach 410yards before hitting the 1600fps expansion threshold?

Based upon my testing of shooting 10 rounds (handloads w/64gr BSB at 2950fps MV) through a chronograph at 5 yards (converting to muzzle velocity) and then shooting 10 more through a chronograph at 100 yards, the G1 B.C. is more like .195 vs. .231 advertised by Nosler. It may actually be even lower (~.175) based upon Winchester's published data shown above.

Bottom line is that I believe your 410yard expansion range is optimistic, likely by ~100yards or so.

[556x45]

DRI,

What velocity did you record at 100 yards?

I am going to try my 27.3 grain CFE223 reload at 100 yards also. I averaging 3050 fps from a 20 inch. It is a slow burning powder and kind of dirty in an AR, especially w a suppressor. You are using H4895 arent you?

Id like to try some. Are you metering or using a powder thrower?

[DRT]

25.0gr H4895. ~2500fps @ 100yards. Each charge is weighed. 7 1/2 rem primer. 2.18" COAL

[556x45]

Thanks DRI. I use the Remington 7 1/2 also. Only one to ignite the CFE uniformly. CCI was too hot and WSR to weak. WSR works with the 75 grain BTHP, so something weird going on there. Win 748 was super accurate in both my rifles but only gave me 2800 fps 16 inch vs up to 2970 fps with CFE223. (I backed off a couple tenths from that however). I'll let you know how I do at 100 yards. Extra velocity will probably burn off quickly and not help that much but its an off-hand carbine load for me. I wold use in in my 20 inch w night vision if I ever go pig hunting. It is a stout little bullet and does not even disintigrate shooting through cinder blocks. My only complaint is that it shoots to left of green tip and higher than the 75 grain ammo. In my rifles anyway. thanks for sharing.

[DRT]

No problem. You're right about the extra muzzle velocity not buying much in terms of expansion range due to the poor B.C. I tuned my load around a 20" douglas match 1x7 bull barrel w/wylde chamber, turned by CLE. I was fortunate that it shoots within 1/2MOA POI in both windage and elevation of my 75gr hornady handload. This barrel is exceptional. I've got a a similar, 16" recon profiled CLE barrel enroute for my LE6920. I hope it performs as well but I expect more, load-to-load POI-shift since it'll likely not be as stiff as the bull barrel (1" diameter to gas block, .925" after gasblock).