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case headspace

fulton armory told me it was Forster.... sounds like they are wrong. I couldn't find it on thier forsters website..
 
ok.. so I cheated. I just picked up feeler gauges at auto parts store.... they are in .001 increments. Started at .010 down to .0015. I guess the FA coaxial M press has more give on their shell holder, typical shell holders have play up and down on the ram. The die bottoms and the shell holder doesn't move..so I don't think it's interfering with the die adjustment. My case OAL is 3.047 FF and I end up with 3.044. So next time I just use .003 gauge and see what happens.

Watched the guy in another video set up his T7 and redding dies do a HS set up with his redding comp shell holders. He went from .010 to .002 and chambered as he went along. I really was liking that !!

So I figured I could try the feeler gauges right? I need to try the .003 next time and see. I did the 5 second count and it held at .001 drop consistently. When at first I didn't count it the case jumped up .003 !

Only thing I forgot to do is take out the firing pin assembly ! Dand Gum it !
 
MASTER CLASS SPORTS, aka MCS INC.
166 POCONO ROAD
BROOKFIELD, CT 06804
(203) 775-1013

No website that I see ...
Yep, That's Mo... He has some unusual hours as well. But a great guy to deal with. He has made me all kinds of custom pic rails too...
 
I go even slower than him in the upstroke, and I wait with the press in the full up position for a 4 thousand count! Been doing it that way for about 25 years and always have had excellent headspace consistency.
did three cases tonight and all three are the same.... FINALLY !
 
What are y'all measuring with? Something I've found changing from Hornady to Whidden to SAC comparators and stacking all of those up against an LE Wilson case gauge and mic is that there is at least a 0.001" of slop if not more in Hornady tools from how poorly the inserts are cut.

The LE Wilson (or RCBS/ Fulton style mentioned earlier) are IMO the most consistent because the body of the case is supported and they use a mic.
Hornady hits the datum different than the mic gauges ? After Using my Hornady gauge, I compare it with my Dillion gauge and it's flush with the high step. Convince me otherwise and I'll buy it ! LOL
 
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Hornady hits the datum different than the mic gauges ? After Using my Hornady gauge, I compare it with my Dillion gauge and it's flush with the high step. Convince me otherwise and I'll buy it ! LOL
Are we talking about two different tools?

I'm referring to the Hornady Lock-n-Load Headspace Comparator. If you have one of those and put a pin gauge in your inserts (or just look at them...) you'll see they're cut rather poorly. If you find it's 0.003" or greater out of round that results in measurements that vary by 0.002" or more, you might decide as I did to find a higher quality, more accurate tool. Nothing at all against the Hornady tool (I have both full sets of comparators, they're probably not going anywhere), it's just that their tolerances aren't great. They also cost half as much as anything else similar, so if you don't want or need more precision, there's nothing to convince you of, keep using the Hornady.

I still use mine for come currently. Guys a lot more practiced in loading and shooting than me use the Hornady tool with great success. (Greg at Primal Rights for example, I think I saw him using one in his die set up video).

I changed because my Whidden die came with a new comparator, and I was getting much more consistent readings with it compared to the Hornady. Instead of rounding off to get the 0.001" repeatable, I was really getting it.

You can run a chamfering tool around them (backwards first) to try to burnishing the edge, or forwards to actually try to cut out some of the eccentricity. They're aluminum though, so be careful.

(I just ordered more pin gauges last week, at some point I'll try to actually show this in a picture)
 
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TL;DR - Don't bother reading if you don't want an ADHD take on cartridge gauges 🤣 Smile and nod and leave the nerdy guy talking to himself alone, he won't hurt you. Unless you startle him, then he might bite. He prefers Reese's Pieces to M&Ms if you need to approach him.


On the off chance you're talking about the Hornady cartridge gauge - that's not a comparator, it's a no-go gauge for SAAMI chamber spec. The LE Wilson case gauge (visually identical to the Hornady and Dillon gauges) and RCBS case mic headspace tools are designed to work with fired brass and measure headspace with a micrometer.

The Dillion gauge shows go/no-go readings for headspace, and has a loose body to accommodate fired brass (at least I'm pretty sure it's for die setup and not a straight ammo checker). The Hornady cartridge gauge can't provide any headspace comparisons because it's designed to not allow brass larger than the SAAMI chamber spec into it, meaning there's no way to compare before and after headspace sizing. It does offer go/no-go for headspace on sized brass, similar to Sheridan Engineering which adds the cutaway view for case length instead of using the gauge body and shows max COAL.

I honestly can't remember if the Hornady cartridge gauge does case length or COAL like the Sheridan off the top of my head, and mine are all at home right now so I can't look. I feel like it does case length because Lyman does case length and I don't have much overlap between those. I might be wrong here. Either way, a cartridge gauge with max trim length spec is really handy since I trim so rarely.

I really like the Sheridan gauges as ammo checkers because of the slot, the visualization it gives is one of the best tools I have for teaching reloading to new guys because they can see everything right there. I need to get a couple actual barrels sectioned like their gauges are, one new and one old. Extend that visualization to measuring distance to lands and how comparators and seating stems interface at different locations along the ogive radius.

The LE Wilson tool is one of my favorites - it does not measure a single datum line reference on the shoulder because it measures from the base. To me that's a more accurate reading of how rounds will fit into an actual chamber - it's essentially hiding the variances in shoulders and in comparator inserts and only showing an average result. So when I can get it down to reading <0.001-0.0005" variance between cases, I'll accept whatever variance the comparator is giving me as a I turn the cases in it because the LE Wilson is confirming that, on average, all of my cases are moving 0.002" or whatever I'm bumping them. The reduced illusion of precision is getting me better accuracy on the die setup.

The same logic extends to the Dillon gauge. In terms of setting up progressive loading machines it's perfect because it uses the full shoulder to verify go/no-go headspace. You'd be at the mercy of using a comparator reading against a chart otherwise, with includes a lot more tolerance errors compared to a chamber style gauge and straight edge IMO.
 
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TL;DR - Don't bother reading if you don't want an ADHD take on cartridge gauges 🤣 Smile and nod and leave the nerdy guy talking to himself alone, he won't hurt you. Unless you startle him, then he might bite. He prefers Reese's Pieces to M&Ms if you need to approach him.
Why did you leave out the gizmatchie that Whidden includes with all his dies for headspace measurements?
(Love to poke the bear!)
(TRANSLATION: gizmatchie = redneck for Shoulder bump gauge)
 
Beat you too it 😜 I actually just added it to the first post - that a Whidden one-off comparator that showed up with my die was ultimately the thing that made me go "hmm this Hornady tool is kind of off" and proceed down a rabbit hole that ultimately doesn't amount to anything other than some theoretical mental gymnastics 🤣

The Hornady tool is perfectly functional in many/ probably most cases. Because ultimately the tolerance ranges of headspace and seating depth are a lot larger than the tolerance slack in the tools we use to measure it.
 
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