Location: a secret lab on the shores of lake titicaca
Posts: 23,063
sinclair comparator
ok i got it from ups,
usage,
it is a little hard to use because it is so easy to put too much pressure on it and accidentally force it too far into the comparator.
the instructions tell you to use a light touch.
and it takes some getting used to as far as the measuring itself because of the numbers you will end up with when measuring nut and all.
BUT
this device along with the others pictured will without a doubt put the bullet EXACTLY where you want the bullet from the lands.
for example.
my chamber is 2.810
i made some rnds. 2.805
is it worth 25 bucks after shipping?
i guess it is.
too late now anyway.
luckily it is impossible to wear out.
__________________ "I don't practice what I preach because I'm not the kind of person I'm preaching to."
Last edited by billy; 03-29-2008 at 08:48 AM.
Reason: Automerged Doublepost
I use one. Funny thing is when I get to the lands and back off a bit in my Model 700 .308, the rounds are too long for the magazine box (using a 168 gn projectile) Dosen't bother me as I use a sled & load one at a time.
OK Billy, I understand the comparator, but something excapes me on the oal gauge, It lookes like a cartridge on a stick and I'm having a hard time seeing how an accurate measurement can be made with it. Could you fill me in?
I swear Billy, you are the greatest. So from what I gather, I need to get the gauge and a modified cartridge, then I put in one of the bullets I'm going to reload and presto I have the exact dem. of my chamber. I guess you know you just cost me some money.....
Location: a secret lab on the shores of lake titicaca
Posts: 23,063
Quote:
Originally Posted by rdale501
I swear Billy, you are the greatest. So from what I gather, I need to get the gauge and a modified cartridge, then I put in one of the bullets I'm going to reload and presto I have the exact dem. of my chamber. I guess you know you just cost me some money.....
THATS THE PROBLEM WITH THESE DAMN FORUMS!
everytime i turn on my computer it cost money!
__________________ "I don't practice what I preach because I'm not the kind of person I'm preaching to."
I drop a bullet into the throat and lightly seat it. I then take a cleaning rod and insert it in the bore, one mark is placed on the rod at the muzzle.
The next measurement is taken with the same rod down the bore with the bolt closed, no projectile, mark again. Take the distance in between (your OAL to the lands) and start to reduce the OAL back from there.
For verification, I use a black dry erase marker on the ogive of the projectile. If I chamber the round and the black dry erase is scuffed, I'm still on the lands. I have always been able to get a few thousandths off the lands by using this method witout touching.
The comparator works well because it gives you an OAL where the projectile will touch the lands, not an OAL on the pointy end of the projectile.
Or you can just take a empty case push a bullet in it so it's long close the bolt up on it about 3 times and you done.
WEll then you did not have [FONT='Calibri','sans-serif']sufficient neck
pressure to hold that bullet I have done it that way for years.But there is nothing wrong with what you have.
[/FONT]
So,jamming the bullet into the riflings a few thousands is cheaper and just as accurate as using guages made specifically for the job? That is intresting. sam.
So,jamming the bullet into the riflings a few thousands is cheaper and just as accurate as using guages made specifically for the job? That is intresting. sam.
Sam, it seems to me they are going back to square one here. The bullet NEEDS to be measured where it hits the lands, not on the tip where the cleaning rod method will touch it...right....wrong....yes no maybe?
Location: a secret lab on the shores of lake titicaca
Posts: 23,063
Quote:
Originally Posted by rdale501
Sam, it seems to me they are going back to square one here. The bullet NEEDS to be measured where it hits the lands, not on the tip where the cleaning rod method will touch it...right....wrong....yes no maybe?
yes rdale.
and i am willing to pay for an EXACT measurement.
i would like to get some other cases in different calibers for my other rifles.
__________________ "I don't practice what I preach because I'm not the kind of person I'm preaching to."
OK Billy you talked me into it. Ordered the modified case and gauge today. Cabelas has some of the cases on sale for 1.88. Ony cal. they had I could use was 25-06 so I got that. Need your thoughts on the comparator though. My neighbor is a mechinist and he thinks he could make the thing. If I'm not wrong the holes are the same dia. as the bore in the rifle. Say .308 for .30 cal. ect. Anyway I don't see as to where the size of the "nut" makes any difference, do you?
Location: a secret lab on the shores of lake titicaca
Posts: 23,063
i just tried to measure my comparator with a caliper and i think the hole might be tapered.
but i dunno....
i dont think the nut size matters but that hole might be something not of this world.
i want to ask MY machinist buddy
(arent they great to have?)
if i can show him the modified case i bought and have him drill and tap a case for every caliber rifle i own!
__________________ "I don't practice what I preach because I'm not the kind of person I'm preaching to."
Last edited by billy; 04-01-2008 at 11:02 PM.
Reason: Automerged Doublepost
i just tried to measure my comparator with a caliper and i think the hole might be tapered.
but i dunno....
i dont think the nut size matters but that hole might be something not of this world.
i want to ask MY machinist buddy
(arent they great to have?)
if i can show him the modified case i bought and have him drill and tap a case for every caliber rifle i own!
Yea Billy, I was thinking the same thing, only I havn't seen one of the cases yet. I have one ordered from Cabelas, I think I'll take it over to him and see what he thinks. I ran the idea behind the comparator by him and he thinks the hole is the same as the bore. I don't know about the taper you talked about, I'll have to give that some more thought.
Just so people don't think I'm some sort of wacko yahoo who won't spend and extra dime on a tool. I'm using the comparator but achieving the same results as far as getting the projectile to the lands then backing off approporiately.
The end result is exactly the same. I have not posted as many reloading stories on G&G and don't claim to be an expert. That said, every load I have assembled in the last 20 years of doing it has been safe, efficient, and of a quality nature.
BTW Sam, the guy who taught me about "jamming" the bullet into the gun (while drinking a beer and playing with myself at the same time ) was an old guy like you. Who incedently has been doing this gig a long time too.
