pls delete
- Thread starter TheCircle
- Start date
FirearmsEnthusiast
CGN frequent flyer
- Location
- Kingston, ON
Are you full-length sizing for your AR?
Sometimes you may need a "small base" resizing die, but typically a properly adjusted full length standard die will resize the base enough to chamber.
Also check length of brass after resizing and trim if necessary. Your case gauge is good for this but I also like to measure with a micrometer.
I suspect you'll need to adjust your full length die down further.
Others will soon chime in as well...
Sometimes you may need a "small base" resizing die, but typically a properly adjusted full length standard die will resize the base enough to chamber.
Also check length of brass after resizing and trim if necessary. Your case gauge is good for this but I also like to measure with a micrometer.
I suspect you'll need to adjust your full length die down further.
Others will soon chime in as well...
Turn the sizer down so far that the shell holder hits it and stops. This means you are getting 100% sizing. Then just try chambering the empty, sized case. If it chambers, seat a bullet (no powder) and check again.
Never had any problems with feeding reloads in any AR and all I do is full length size with regular dies...As well I am just sizing enough so that I am bumping the shoulder back about a thou for better brass life span in regards to case stretch and resulting head separation.
Sounds like if you have tried adjusting your FL die to no avail you my need small base FL die for your particular chamber just like Enthusiast said...Good luck.
Sounds like if you have tried adjusting your FL die to no avail you my need small base FL die for your particular chamber just like Enthusiast said...Good luck.
If you are using the same brass fired in your Remington 700 to use in your AR15 you may have a brass spring back problem.
You can try pausing at the top of the ram stroke for 4 to 5 seconds to reduce brass spring back.
If that does not work you may need a small base die that reduces case diameter and pushes the case shoulder back .003 more than a standard die.
This is where having a vernier caliper and the Hornady cartridge case headspace gauge. This will allow you to measure case diameter and base to shoulder measurement.
Below the red JP Enterprise case gauge is made with a finish chamber reamer and smaller in diameter than the Wilson and Dillon case gauges. As you can see the reversed cases drop further into the Wilson and Dillon gauges. Meaning the JP Enterprise gauge is closer to minimum SAAMI diameter.
Below measuring a "FIRED" .223/5.56 case in my Hornady gauge first before sizing and then set the die up for .003 to.004 shoulder bump.
NOTE, on a semi-auto the resized case needs to be .003 to .005 smaller in diameter than its fired diameter for reliable extraction. This makes the case spring back from the chamber walls after firing and not drag and bind on the chamber walls.
You can try pausing at the top of the ram stroke for 4 to 5 seconds to reduce brass spring back.
If that does not work you may need a small base die that reduces case diameter and pushes the case shoulder back .003 more than a standard die.
This is where having a vernier caliper and the Hornady cartridge case headspace gauge. This will allow you to measure case diameter and base to shoulder measurement.
Below the red JP Enterprise case gauge is made with a finish chamber reamer and smaller in diameter than the Wilson and Dillon case gauges. As you can see the reversed cases drop further into the Wilson and Dillon gauges. Meaning the JP Enterprise gauge is closer to minimum SAAMI diameter.
Below measuring a "FIRED" .223/5.56 case in my Hornady gauge first before sizing and then set the die up for .003 to.004 shoulder bump.
NOTE, on a semi-auto the resized case needs to be .003 to .005 smaller in diameter than its fired diameter for reliable extraction. This makes the case spring back from the chamber walls after firing and not drag and bind on the chamber walls.
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I tried that its still just a bit too tight. Its also way below the minimum on the dillon case cage.
If you are using the same brass fired in your Remington 700 to use in your AR15 you may have a brass spring back problem.
You can try pausing at the top of the ram stroke for 4 to 5 seconds to reduce brass spring back.
If that does not work you may need a small base die that reduces case diameter and pushes the case shoulder back .003 more than a standard die.
This is where having a vernier caliper and the Hornady cartridge case headspace gauge. This will allow you to measure case diameter and base to shoulder measurement.
Below the red JP Enterprise case gauge is made with a finish chamber reamer and smaller in diameter than the Wilson and Dillon case gauges. As you can see the reversed cases drop further into the Wilson and Dillon gauges. Meaning the JP Enterprise gauge is closer to minimum SAAMI diameter.
Below measuring a "FIRED" .223/5.56 case in my Hornady gauge first before sizing and then set the die up for .003 to.004 shoulder bump.
NOTE, on a semi-auto the resized case needs to be .003 to .005 smaller in diameter than its fired diameter for reliable extraction. This makes the case spring back from the chamber walls after firing and not drag and bind on the chamber walls.
I am using a mix between brass already fired out of my AR and cleaned range brass. My once fired rem 700 brass goes in its own container.
DiabeticKripple
CGN Regular
- Location
- Red Deer, Alberta
Might just have a tight chamber in your AR15 and need to try small base dies.
Chambers and dies vary in size and problems like yours happen all the time.
I buy bulk once fired military Lake City cases that were fired in hundreds of different rifles. The first time I resize these cases I use a small base die and thereafter I use a standard die.
I'm loading for three different AR15 rifles and I check all the loaded rounds with my JP Enterprise gauge that is smaller in diameter than a Wilson or Dillon case gauge.
So again having a vernier caliper to take case measurements of the fired case and after sizing will tell you a great deal.
From what I have read from your posts you do not have a cartridge headspace issue. Meaning shoulder to base measurement and it sounds like a case diameter problem.
Below the JP Enterprise is cut with a Wylde finish reamer and if the case fits this gauge it will chamber in any rifle. The Wilson and Dillon gauges are cut closer to maximum SAAMI diameter or even larger. And again your sized cases need to be .003 to .005 smaller in diameter than their fired diameter for a semi-auto.
I would also buy a RCBS AR Series small base die set with a taper crimp seating die. This will size your range pickup brass back to minimum SAAMI dimensions.
AR Series Die Set Features:
Designed for AR-style and semi-auto rifles
Distinctive black RCBS® die box
Small Base sizing
Taper Crimp bullet seating
RCBS® Limited Lifetime Warranty
I buy bulk once fired military Lake City cases that were fired in hundreds of different rifles. The first time I resize these cases I use a small base die and thereafter I use a standard die.
I'm loading for three different AR15 rifles and I check all the loaded rounds with my JP Enterprise gauge that is smaller in diameter than a Wilson or Dillon case gauge.
So again having a vernier caliper to take case measurements of the fired case and after sizing will tell you a great deal.
From what I have read from your posts you do not have a cartridge headspace issue. Meaning shoulder to base measurement and it sounds like a case diameter problem.
Below the JP Enterprise is cut with a Wylde finish reamer and if the case fits this gauge it will chamber in any rifle. The Wilson and Dillon gauges are cut closer to maximum SAAMI diameter or even larger. And again your sized cases need to be .003 to .005 smaller in diameter than their fired diameter for a semi-auto.
I would also buy a RCBS AR Series small base die set with a taper crimp seating die. This will size your range pickup brass back to minimum SAAMI dimensions.
AR Series Die Set Features:
Designed for AR-style and semi-auto rifles
Distinctive black RCBS® die box
Small Base sizing
Taper Crimp bullet seating
RCBS® Limited Lifetime Warranty
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