Custom comparator inserts

[Lkwebb]

I just received my new custom inserts from www.shortactioncustoms.
Each insert is cut just like your chamber shoulder.. so you get more precise shoulder measurements when bumping the shoulders.
The kit with 4 inserts are 150.00 with comparator body and stand...
I measured some 6.5 brass with my hornady comparator and then used SAC comparator. Quite a bit if difference but you would expect it to with the SAC being cut to the degree of the shoulder...
Each insert snaps in place ..

 

[Dusty Stevens]

That looks like a great tool.

 

[whatsupdoc]

Been using the Brownells equivalent for years, the SAC ones look great.

 

[Metal God]

Can you explain what the differences is ? Are you saying you are getting very inconsistent measurements with your Hornady tool and more consistent measurements with the new tool from case to case ??

I always thought the comparator was designed to compare one case to the next case and not one case to your chamber .

I have both Hornady and Sinclair inserts and the measurements they give are incredibly different from one another . However they both do the exact same job as far as comparing one case to the next equally and accurately .

I might not be understanding what you mean though by difference in the two .

 

[Dusty Stevens]

Can you explain what the differences is ? Are you saying you are getting very inconsistent measurements with your Hornady tool and more consistent measurements with the new tool from case to case ??

I always thought the comparator was designed to compare one case to the next case and not one case to your chamber .

I have both Hornady and Sinclair inserts and the measurements they give are incredibly different from one another . However they both do the exact same job as far as comparing one case to the next equally and accurately .

I might not be understanding what you mean though by difference in the two .

thats all they do is give you a measurement to "compare"- the measurements vary even from tool to tool of the same brand so use the same exact tool. this tool should give a more reliable measurement with more surface area. its the same style as the gizzys we've used in benchrest since the beginning (we use the actual chamber reamer), but instead of being multi piece and attaching to the calipers its just a little handheld widget.

 

[Mad_Charlie]

thats all they do is give you a measurement to "compare"- the measurements vary even from tool to tool of the same brand so use the same exact tool. this tool should give a more reliable measurement with more surface area. its the same style as the gizzys we've used in benchrest since the beginning (we use the actual chamber reamer), but instead of being multi piece and attaching to the calipers its just a little handheld widget.

Yes, it is the increased surface area that will give more consistent results, and less worry about measurements changing over time due to wear.

 

[JimSC]

Yes, it is the increased surface area that will give more consistent results, and less worry about measurements changing over time due to wear.

don' know about the wear part, it's not like the inserts are a high use item. The case will be more stable in the tool due to the increased contact area of the shoulder area, but for 150 bucks I will just keep rotating the case and double checking my measurements

 

[Mad_Charlie]

Wear comes from rotating the case as you get a good "feel" in the calipers.
That sharp edge gets "dulled" fairly quickly. Aluminum is soft. A larger area of contact lasts longer. Doesn't apply as much if using stainless inserts.

I guess I was thinking about an extended time period as the insert slowly wears away at the edge.

Since I have been making my own inserts from stainless for a few years now, I don't/didn't really consider the cost.

 

[JFrank]

Just as a parallel I started using the 30 cal insert on the Hornday comparator for measuring my 6 bra shoulder set back and I gotta say - I like it....

 

[JimSC]

Wear comes from rotating the case as you get a good "feel" in the calipers.
That sharp edge gets "dulled" fairly quickly. Aluminum is soft.

and exactly how much wear occurs between measuring a case, sizing it and remeasuring to see if the die is set correctly ? Also aluminums softness depends on the alloy, just like any metal different alloys have different properties. (edit)7075 aluminum has a brinell hardness of around 150

 

[Metal God]

i think you get some wear with the aluminum inserts at first but believe it stops relatively quickly . I use them all the time on hundreds of cases a year as far as I can tell they’re pretty much settled in to a consistent measurement

 

[Mad_Charlie]

and exactly how much wear occurs between measuring a case, sizing it and remeasuring to see if the die is set correctly ? Also aluminums softness depends on the alloy, just like any metal different alloys have different properties. (edit)7075 aluminum has a brinell hardness of around 150

No kidding Jim, I have been working with almost exclusively with various aluminum alloys for the last 20 years. Both machining and welding.

I am finished with this conversation. You have beaten me bloody, I am only a shadow of my former self. I will always remember to never again engage in conversation with the great JimSC. The whole issue is really not that important enough to get in to extended arguments over. and I really don't care.

 

[skeeljc]

The Sinclair inserts have a long shoulder that matches the case angle.

 

[JFrank]

The Sinclair inserts have a long shoulder that matches the case angle.

In theory yes however I’ve a comparator with a fundamental difference in angle, drove me to the curb.. the chamber reamer cuts a matching angle Sinclair.... maybe not so much.

 

[PhilC]

The Sinclair inserts have a long shoulder that matches the case angle.

And Sinclair inserts are stainless steel too.