Brass from my AR

[ALBY]

Should I process as normal (trim, full length re size ?) or is there advantage to fireformed brass in an autoloader ?

 

[BFMIN]

Most self-loaders can't apply the loading force that the cams in a bolt action so I'd go with full length resizing. Other than that & making doubly certain you primers are flush or below the base to prevent slam fires I'd say proceed as normal.

 

[Deep Creek Rock]

Should I process as normal (trim, full length re size ?) or is there advantage to fireformed brass in an autoloader ?

Semi & Full Auto fire need full size resizing - to insure feeding. Neck sizing is only for bolts, and single shot break open guns. The case needs to be fully resized in a Semi auto to ensure it feeds & chambers freely. Some AR's may require small base dies - these dies actually resize the case to smaller than SAAMI specs- again to ensure it feeds & chambers. Not all guns need them -it varies by make.

One of the reasons why Semi Auto', can be a disadvantage, when it comes to the accuracy game is that they need to be full length resized - and the bullet crimped. Some people say they dont crimp - but it is recommeded that you do on military / semi autos. Bullets can be pushed further into the case on a round that is not crimped, from impacting the feed ramp. This can spike case pressure - and possibly cause a case rupture. Most bullets that are intended to be fired in AR's/ Semi Auto have cannelure to crimp the bullet. Crimping a bullet with no cannelure - degrades accuracy!

I would most defintely trim your brass as well. Its a good idea to measure your cases and see if they over spec. Too long a case, can rupture -as there is no place for the brass to flow.

If the rounds you bought were military / 5.56 Nato - the primer pockets will more than likely have a crimp - and need to be swaged, so that when you prime. the primer seats fully. A high primer can actually cause a round to fire off when you close the action / bolt.

 

[Russ D]

I don't crimp but I also regularly check for set back.

 

[rseymorejr]

Semi & Full Auto fire need full size resizing - to insure feeding. Neck sizing is only for bolts, and single shot break open guns. The case needs to be fully resized in a Semi auto to ensure it feeds & chambers freely. Some AR's may require small base dies - these dies actually resize the case to smaller than SAAMI specs- again to ensure it feeds & chambers. Not all guns need them -it varies by make.

One of the reasons why Semi Auto', can be a disadvantage, when it comes to the accuracy game is that they need to be full length resized - and the bullet crimped. Some people say they dont crimp - but it is recommeded that you do on military / semi autos. Bullets can be pushed further into the case on a round that is not crimped, from impacting the feed ramp. This can spike case pressure - and possibly cause a case rupture. Most bullets that are intended to be fired in AR's/ Semi Auto have cannelure to crimp the bullet. Crimping a bullet with no cannelure - degrades accuracy!

I would most defintely trim your brass as well. Its a good idea to measure your cases and see if they over spec. Too long a case, can rupture -as there is no place for the brass to flow.

If the rounds you bought were military / 5.56 Nato - the primer pockets will more than likely have a crimp - and need to be swaged, so that when you prime. the primer seats fully. A high primer can actually cause a round to fire off when you close the action / bolt.

So I recently finished assembling My AR and have been saving the brass with the intention of reloading.
How can I tell if I will need small base dies? my barrel is from Del-Ton.

 

[Deep Creek Rock]

Most people use the standard Full length dies - and they generally work fine. The small base dies are really for "special cases", when the standard full length resized rounds wont chamber.

However ,RCBS now makes a die set geared towards AR's - The "AR series". It is a small base die set, includes a seater die with taper crimper.

Aside from doing a chamber casting - I would be inclined to contact the manufacter of the barrel, and find out it has been reamed under SAAMI spec.