i got these for free, i think i know what they are

[AXEMAN]

but im not sure.

but this is what i think you do with it.

ive no idea what its called, possibly a comparator? i use it to measure off the ogive right? now do i take a bunch of bullets that are my desired OAL and then use this to measure them at that point and average that and use it as a measure for my base cartridge length since the tips can be damaged. am i close here at all? cause really, i have no idea. its been in the tool box since i bought it, it was a freebie. is there a big book of this stuff? can ya school me?

 

[LoneWolfUSMC]

Re: i got these for free, i think i know what they are

Yep.

If you don't need em, send em to me! I have actually been looking at that set or the ones Sinclair sells. I believe the ones you have are Hornady.

 

[slayer_21420]

Re: i got these for free, i think i know what they are

That is a stony point bullet comparator, it can be used for a few different things, I use mine to check bullet seating depth as measuring off the tip you will vary by as much as .020"ish
can also be used for bullet sorting but I don't get that in depth

Steve

 

[ChrisGarrett]

Re: i got these for free, i think i know what they are

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Slayer_21420</div><div class="ubbcode-body">That is a stony point bullet comparator, it can be used for a few different things, I use mine to check bullet seating depth as measuring off the tip you will vary by as much as .020"ish
can also be used for bullet sorting but I don't get that in depth

Steve </div></div>

I used to buy bullets off of Ebay and collected a few boxes each of 7mm 168 SMKs and 7mm Hornady 162gr HPBT National Match. Just looking at the boxes, one can tell that they're years apart. Hornady even dates their stuff, or did back then.

I started working on a 1k load and decided to use the SP/Hornady comparator and measure the two tips. Shit if they weren't all over the map.

I could almost create a time line where Hornady and Sierra changed the shapes of these two bullet models. There was a large difference in ogive lengths to both types, from box to box, year to year.

Chris

 

[USMCj]

Re: i got these for free, i think i know what they are

Looks just like my Hornady bullet comparator set. You can do 2 things with that.

1. Check just the bullets to see how consistent the base to ogive length is

2. Check the OAL of a loaded round from the base of the cartridge to the ogive (just like in pic #2)

But make sure you use the correct bushing for each caliber.

 

[AXEMAN]

Re: i got these for free, i think i know what they are

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: USMCj</div><div class="ubbcode-body">Looks just like my Hornady bullet comparator set. You can do 2 things with that.

1. Check just the bullets to see how consistent the base to ogive length is

2. Check the OAL of a loaded round from the base of the cartridge to the ogive (just like in pic #2)

But make sure you use the correct bushing for each caliber. </div></div>

ok looking at the pictures you can see the stamps on each silver part. 8-30 is 30 caliber im guessing? i have no instructions, so i just went from other pictures i have seen. i hadnt looked at them in months after getting them when it dawned on me that 8-30 was 30 caliber. i was just sitting there watching tv and i had to go look at them and see.

is there a list somewhere of base to ogive measurements on different bullets or do you calculate that measurement like i mentioned in the OP?

no markings on this so i dont know the brand. geez how many more ways can they throw in another reason to do more math, lol?

 

[USMCj]

Re: i got these for free, i think i know what they are

No list. That tool is to allow you to measure base to ogive on bullets so you can weed out the oddball bullets that are way off.

 

[ryder198]

Re: i got these for free, i think i know what they are

they are used to measure from the o-give as stated about. It is the most accurate way to measure case OAL. ogive to tip measurements chage, especially on HT bullets. THe ogive is the first part of the round to touch the lands so it really is useless to measure form the tip for OAL. Hornady anbd Stony point are the same. ONe made by or for the other.

TO use just put on the caliper and zero it out. Measure a known accurate round and set the rest to the same.

 

[ChrisGarrett]

Re: i got these for free, i think i know what they are

They're great tools to have. Be all you can be and get the headspace inserts as well.

Here's a tip I do when using either the SP/Hornady/Sinclair dohickeys for headspace, OAL and bullet comparison with those tools.

Since we're dealing legimately in thousandths of an inch .001" with this tool, it's important to get it right. The red (green for Sinclair) holders you see, for both headspace and OAL/Bullets can be machined slightly off, same with the inserts.

I take my insert bodies (have two) and put the first insert in and make a single, vertical witness mark up from the body and onto the insert. It doesn't matter where that witness mark is, just make it. I use a Sharpie maker, which doesn't rub off easily.

Take the second insert and cinch it down and follow that mark on the body up and onto it. Repeat, sip beer, repeat, sip beer.

You will get variations in your measurements just throwing those things in there, I've noticed with both my kits. I've seen at least a couple of thous difference with this insert, or that insert, just rotating them within the holder.

The witness mark at least allows you to be in a better position to be a tad more consistent and repeatable. And it's FREE!

Chris