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Discussion Starter · #1 ·
Okay, I'm almost there on being ready to try my hand at reloading. There are already enough threads on what powder, primers, and slugs to use, that I will probably just have to jump in and see what happens.

My questions are more on the specifics of which recipes to follow. Is there any difference in thickness or other specs between .223 and 5.56 headstamp brass? I don't want to overpressure a shell with a 5.56 recipe and run into trouble there. I would think that for plinking, I will tend toward .223 to use less powder, but knowing is never bad, especially when preventing overpressure.

In the other direction, is there any fundamental difference between the primer cup in a .223 and a 5.56 case, once the primer is removed, and the cup swaged? I am seeing standard, magnum, and military primers. Overall questions:

  • Will one of these types of primers or another trap me into one caliber headstamp or another?
    Will one of them require me to reapply a primer cup crimp to the finished round after loading?

Finally, what is everyone's opinion on cannelure? Considering my previous experience with setback in other rounds, I think it sounds like a good idea. Is any additional equipment required to apply the crimp, or is this accomplished within the die?

Thanks,
Scott
 

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Any small rifle primer will work for 223/5.56. Military brass case walls are thicker so if you put the same charge in a NATO case as you do in a commercial 223 case your internal pressure will be greater because the internal volume of the case on NATO is smaller. If you are using military brass the crimp in the primer pocket needs to be reamed out before it will fit a commercial Small Rifle primer. I have used all brands except Wolf and had good reults. I have used Small Rifle Magnum primers in 223 loads also but backed off the load 10% to be safe. I would suggest selecting the powder you intend to use load 5 rounds of several different loads going from minimum load to near maxand then test fire each 5 rounds to see which shoot the tighter group, then stick with that load for max accuracy. Here's my last test at the range, roughly 1MOA group-

The 75gr Hornady loads are Skypup's recipe using 25gr BLC-2 powder and Remington 7 1/2 SR primers. Hope this helps you.
 

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saw9000 said:
Finally, what is everyone's opinion on cannelure? Considering my previous experience with setback in other rounds, I think it sounds like a good idea. Is any additional equipment required to apply the crimp, or is this accomplished within the die?

Thanks,
Scott
Forget the cannelure and the crimp - you do not need it and it will decrease accuracy anyways....
 

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Discussion Starter · #4 ·
Okay, so overall, the specs on the case are the same, other than the internal volume where the powder is stored. I will definitely take the advice on walking up and down the recipe range to see what works best.

On the cannelure, how does it decrease accuracy? I ask because I have had enough trouble with setback on .357 Sig that I would like to try crimping. It would be easier to know on the front end if I need to avoid it altogether.

Thanks,
Scott
 

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Any cannelure bullet will be less accurate compared to the same bullet without any cannelure just due to the air friction it creates and the increased tension.

So far I have loaded over 4,000 full power 5.56mm rounds for both my SIG 556s without using any cannelure or crimp and have never had any problems with bullet seating or setback. The bullets I use are the 75 grain BTHP from Prvi or Hornady or Nosler without cannelure and they are all maximum length rounds and shoot perfectly.

You can certainly use cannelure bullets with a crimp but you certainly do not need to....
 

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You can also taper crimp the non canelure bullets if you like for extra assurance. Sometimes I do this with the BTHP Match bullets.
 

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saw9000 said:
Finally, what is everyone's opinion on cannelure? Considering my previous experience with setback in other rounds, I think it sounds like a good idea. Is any additional equipment required to apply the crimp, or is this accomplished within the die?
Your sizing die with its internal expander ball should yield you enough resulting tension between the bullet and case to prevent setback. That said, I always crimp the 55gr and 62gr FMJ bullets that come with cannelures.

Roll crimps are the traditional method of crimping bottle necked rifle cartridges. Most seating dies include the roll crimp. Although you can roll crimp and seat at the same time if everything is setup perfectly, I would definitely suggest seating in one step and then roll crimping in a seperate step. You'll most likely get better results. You'll also need to trim all your cases to the same length. Otherwise you'll get some with less and others with more crimp.

In my opinion, a better crimping option is available from Lee. It's called their factory crimp die for bottle necked rifle cartridges. It forms a crimp that is more like factory ammunition and is not as sensitive to trim length. The Lee FCD is pretty inexpensive, so I think it's worth the investment. I have one for 5.56x45, 7.62x39, and 7.62x51. Note: Please do not take my endorsement of the Lee FCD for bottle necked rifle cartridges as an endorsement of their FCD for pistol cartridges. The FCD for pistol cartridges post sizes completed cartridges which is a bad idea in my opinion because it is frequently used to cover up poor reloading practices.
 
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