I recently decided to try making more accurate 556 ammo by sorting brass, measuring shoulder from cases fired in my rifle, using bushing and micrometer dies, etc. Unfortunately, unlike my other Sinclair bump gage inserts, the 556 #23 will not pass over the case mouth of brass from my AR. It works as it should on new or sized brass. I only have the full length bushing die. Did I get the wrong insert? It really does me no good if it doesn’t fit fired cases. I have inserts for 338 Lapua, 308, and 6.5 Grendel and all work on fired brass as they should.
Problem with bump gauge insert
- Thread starter thedude824
- Start date
23 degrees is the correct insert. Couple of things could be going on, but it sounds like your chamber (223 Wylde?) has a larger neck diameter than the gauge insert ID.
Can you measure the OD of the neck on undented fired brass?
Can you measure the OD of the neck on undented fired brass?
Call the manufacturer and see if they can help. It sounds like the diameter of the bore in the gauge is too small.
Take your calipers, and check the ID of the end of the gauge insert that goes into the 'body'. See what that measures.
I just walked out to the shop, and checked mine: it measures 0.274" inside - which should be *plenty* for any brass coming out of a .223 / 5.56 chamber.
Unless it's been dented or otherwise deformed. ARs do tend to be hard on the case mouths/necks to begin with, but sometimes brass gets flung into a concrete wall, or stepped on, and then all bets are off as far as it 'fitting' in anything until it's been through a sizing die. I'm assuming you're bright enough to not try to measure one of those, and then complain about it here
I just walked out to the shop, and checked mine: it measures 0.274" inside - which should be *plenty* for any brass coming out of a .223 / 5.56 chamber.
Unless it's been dented or otherwise deformed. ARs do tend to be hard on the case mouths/necks to begin with, but sometimes brass gets flung into a concrete wall, or stepped on, and then all bets are off as far as it 'fitting' in anything until it's been through a sizing die. I'm assuming you're bright enough to not try to measure one of those, and then complain about it here
I’ll do it as soon as I get home. It’s once fired Lake City 556. It came from a Criterion Hybrid so I’ll check to see what chamber they use. It is 223 Wylde.
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I’ll check as soon as I get home. I also thought it could be a one off but I checked 30 pieces. Not a single one would fit without significant force which would likely jam it into the gage.Take your calipers, and check the ID of the end of the gauge insert that goes into the 'body'. See what that measures.
I just walked out to the shop, and checked mine: it measures 0.274" inside - which should be *plenty* for any brass coming out of a .223 / 5.56 chamber.
Unless it's been dented or otherwise deformed. ARs do tend to be hard on the case mouths/necks to begin with, but sometimes brass gets flung into a concrete wall, or stepped on, and then all bets are off as far as it 'fitting' in anything until it's been through a sizing die. I'm assuming you're bright enough to not try to measure one of those, and then complain about it here
Lol! I was honestly hoping it was me being an idiot, but I can’t see how it’s operator error yet. Every piece I tried had a neck and mouth with no visible damage/abnormalities. I’d hate to have to buy a neck sizing die that I’ll never use just to get shoulder bump set for this rifle.
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