For a AR-10 do you need to use small base dies? If YES is this only used if the first round was from range brass from a machine gun or is it a die that should alsways be used ? THANKS !!!!
- Thread starter Herd Thinner
- Start date
Never used SB dies for my son's ARs, over 2K rounds in 2 yrs and no fails.
For ARs I always use small base dies the first time I reload once fired brass from another gun. After that I just use regular dies. I reload for my buddys AR10 and have found an occasional LC brass that was tight when initially sizing it. I can only guess that some of it was fired from a MG due to how much extra force it took to size over the rest of the lot. Its not a big deal but could cause problems the first time around if youre not using a SB die.
I have a barrel from a DPMS in the garage with a stuck case in it, I now own a set of SB X dies from RCBS for 223 and 308, I also had to install a new 18inch med wt barrel on that DPMS
I brought mine to a local gun smith. He dropped some lube and used for sips to extract the case. I guess I need to start tearing down brass.
There is a better way . . . .
Herd Thinner . . . .
I recommend looking at the Digital Headspace Gauge.
Small Base dies are very rarely needed. They are often used as a last resort when handloads don't chamber properly. However, the remedy is to measure the shoulder clearance that YOUR handloads have in YOUR particular chamber. Knowing that shows how to accurately set your die height, and that will solve your problem.
Look into the Digital Headspace Gauge. It displays this information by pressing one button. You can set the die height perfectly for your chamber - not according to a drop gauge or some cartridge drawing.
Herd Thinner . . . .
I recommend looking at the Digital Headspace Gauge.
Small Base dies are very rarely needed. They are often used as a last resort when handloads don't chamber properly. However, the remedy is to measure the shoulder clearance that YOUR handloads have in YOUR particular chamber. Knowing that shows how to accurately set your die height, and that will solve your problem.
Look into the Digital Headspace Gauge. It displays this information by pressing one button. You can set the die height perfectly for your chamber - not according to a drop gauge or some cartridge drawing.
A military type chamber is .0025 larger in diameter than a standard SAAMI chamber and a "standard" full length resizing die should work fine "BUT".............
1. I use small base dies when picking up once fired range brass or buying once fired brass to return the case to minimum dimentions. Also note that small base dies only size the case .0005 to .001 smaller in diameter but they size further down the case.
You will need to determine the diameter of your chamber or measure your fired cases for expansion. The general thumb rule for semi-autos is to use a small base die for 100% reliable feeding and and extraction also remember the headspace is set longer on these type rifles so measure your fired cases and set up your dies for the proper shoulder bump.
As an example I have two AR15 rifles and a bolt action .223, my AR15 carbine has the largest chamber, my AR15 A2 HBAR has a slightly tighter chamber and the bolt action is the smallest and a standard SAAMI chamber.
As you can see below there is .0035 difference between the smallest diameter and largest diameter chambers and some of these rifles have the tighter match type chambers. Bottom line, nothing is written in stone and you will need to find out what your rifle likes.
1. I use small base dies when picking up once fired range brass or buying once fired brass to return the case to minimum dimentions. Also note that small base dies only size the case .0005 to .001 smaller in diameter but they size further down the case.
You will need to determine the diameter of your chamber or measure your fired cases for expansion. The general thumb rule for semi-autos is to use a small base die for 100% reliable feeding and and extraction also remember the headspace is set longer on these type rifles so measure your fired cases and set up your dies for the proper shoulder bump.
As an example I have two AR15 rifles and a bolt action .223, my AR15 carbine has the largest chamber, my AR15 A2 HBAR has a slightly tighter chamber and the bolt action is the smallest and a standard SAAMI chamber.
As you can see below there is .0035 difference between the smallest diameter and largest diameter chambers and some of these rifles have the tighter match type chambers. Bottom line, nothing is written in stone and you will need to find out what your rifle likes.
Best Handloading Technique . . . . it's simple too.
CASE WIDTH . . . .
All non-belted rifle cases fully expand to chamber diameter, and that leaves a visible change in case diameter. It makes very little difference where your brass comes from if you can resize it accurately. This requires measuring case to chamber clearance (above the web) with an ordinary set of calipers, using the wide part of the blades. (1)Zero your calipers just above the web on one of your fired cases. (2) Then measure your handloads in the same way. Your calipers will display the exact chamber clearance that YOUR handloads have in YOUR chamber.
CASE LENGTH . . . .
Most shooters don't measure their "shoulder to chamber" clearance either. When doing this, you ALSO need to know the actual size of YOUR particular chamber. Otherwise you are comparing handloads to something that may not accurately represent YOUR particular chamber. That is the main advantage of the Digital Headspace Gauge. It can also measure your bullet to rifling jump within a thousandth of an inch, and it works on ALL different calibers without any attachments.
CASE WIDTH . . . .
All non-belted rifle cases fully expand to chamber diameter, and that leaves a visible change in case diameter. It makes very little difference where your brass comes from if you can resize it accurately. This requires measuring case to chamber clearance (above the web) with an ordinary set of calipers, using the wide part of the blades. (1)Zero your calipers just above the web on one of your fired cases. (2) Then measure your handloads in the same way. Your calipers will display the exact chamber clearance that YOUR handloads have in YOUR chamber.
CASE LENGTH . . . .
Most shooters don't measure their "shoulder to chamber" clearance either. When doing this, you ALSO need to know the actual size of YOUR particular chamber. Otherwise you are comparing handloads to something that may not accurately represent YOUR particular chamber. That is the main advantage of the Digital Headspace Gauge. It can also measure your bullet to rifling jump within a thousandth of an inch, and it works on ALL different calibers without any attachments.
