DaveT Posted January 31, 2012 Report Share Posted January 31, 2012 I have been happily using the Hornady bullet comparator bushing tool to measure COL at the Bullet Ogive for a LONG time. Recently I decided that I would buy a second set of bullet comparator bushings in case I lost my originals....so far so good! Just used my 260 Rem (New) comparator bushing and found that it gives me an ogive reading on the same 123g scenar bullets that is .006'' greater than the original bushing.... bugger...so much for repeatability!!! My original reading to get just onto the lands is clearly not valid across what should be two identical comparator bushings. Has anyone else had similar results? Link to comment Share on other sites More sharing options...
Gunsgobang88 Posted January 31, 2012 Report Share Posted January 31, 2012 Hi Dave, It's just that, a comparator. It's useful for establishing seating depth after getting a bullet just touching the rifling and taking measurements from that particular cartridge. If you wish to be more precise, turn up new inserts from a section of barrel of the required calibre, Cheers Alan Link to comment Share on other sites More sharing options...
DaveT Posted February 1, 2012 Author Report Share Posted February 1, 2012 Hi Dave, It's just that, a comparator. Its useful to establish seating depth after getting a bullet just touching the rifling and taking measurements from that partcular cartridge. If you wish to be more precise, turn up new inserts from a section of barrel of the required calibre, Cheers Alan Alan thanks for the feedback... I had just taken it for granted that they had been manufactured to an accurate & consistently standard dimension. I guess the lessons are (A) Take nothing for granted & ( make sure that you use the same comparator insert for both OAL measurement and bullet seating. Link to comment Share on other sites More sharing options...
clivej Posted February 1, 2012 Report Share Posted February 1, 2012 Before I got the Hornady comparator I had an 'Unknown make' and a Hornady 30 cal VMax would fall right into it. That went into the bin along with a 224 size, now using Hornady. Link to comment Share on other sites More sharing options...
jon Posted February 18, 2012 Report Share Posted February 18, 2012 must have been lucky ... when I was checking seating depth I coated the bullet with black felt tip. checked the rifling marks against the "comparator" and got a 'match'. Also found that a case that had just been over a neck turning Mandrel also 'fitted'. But was given a spare that sat almost 1mm lower on the bullet .. something about 'manufacturers tolerances' ? ... would have been an interesting jam fit! Link to comment Share on other sites More sharing options...
Davy Posted February 18, 2012 Report Share Posted February 18, 2012 I make my own and try to match them as closely as possible to the point the bullet is engraved in the barrel. I keep hem safe and have never built a second in any size for myself in case they got mixed up. Link to comment Share on other sites More sharing options...
Andrew Posted February 19, 2012 Report Share Posted February 19, 2012 With Hornady you're lucky they got that close! I've been after them about a set of reloading dies I purchased a year and a half ago that has never turned out a correct loaded round of ammo. Their manufacturing tolerances tanked on my dies, at least. I'm not happy with them. ~Andrew Link to comment Share on other sites More sharing options...
TonyH Posted February 19, 2012 Report Share Posted February 19, 2012 Presumably this is about some other kind of comparator than the type currently branded as Hornady but which I bought years ago as the Stoney Point tool. Always find mine very reliable and consistent if used in a consistent way - especially using a custom-made "modified case" that's one of my once-fired Lapua/Dakota 20Tac jobs(thanks Dave). The only other similar device I've owned was the RCBS Precision Mic in 22-250, excellent tool, wish they did one in 20-cal... Tony Link to comment Share on other sites More sharing options...
DaveT Posted February 19, 2012 Author Report Share Posted February 19, 2012 Presumably this is about some other kind of comparator than the type currently branded as Hornady but which I bought years ago as the Stoney Point tool. Always find mine very reliable and consistent if used in a consistent way - especially using a custom-made "modified case" that's one of my once-fired Lapua/Dakota 20Tac jobs(thanks Dave). The only other similar device I've owned was the RCBS Precision Mic in 22-250, excellent tool, wish they did one in 20-cal... Tony My original post was about the differences between same-calibre comparator inserts which returned quite different measurements. I had expected them to be identical when I bought 'spares'. I am very happy with the tool itself but the lesson learned was to make sure that whatever bullet comnparator you used to measure Max OAL was also used to measure your loaded rounds..... 2 of the 'same' comparators are clearly not identical! Link to comment Share on other sites More sharing options...
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