How to measure headspace without tools?
- Thread starter vitaminb
- Start date
Easy. You don't.
No tools, equals you have not measured anything.
All you get by coating a case with soot, is soot in your chamber, and still no idea if the actual headspace is correct or not.
Consider this. How do you know that the cartridge you are using is correct?
Read the SAMMI specs that show the size variation between min and max cartridge size, as well as min and max chamber size for your caliber, and you will rapidly see (maybe) why using a cartridge, fired or otherwise, is a crappy solution.
Buy a headspace gauge, make one, or talk to someone that has them, in order of however you see fit. Making one, of course, requires that you know the dimensions, and are able to machine to them, whether it's with a lathe, or a grinder.
Sooo... Why do you see fit to measure the headspace in the first place?
Cheers
Trev
No tools, equals you have not measured anything.
All you get by coating a case with soot, is soot in your chamber, and still no idea if the actual headspace is correct or not.
Consider this. How do you know that the cartridge you are using is correct?
Read the SAMMI specs that show the size variation between min and max cartridge size, as well as min and max chamber size for your caliber, and you will rapidly see (maybe) why using a cartridge, fired or otherwise, is a crappy solution.
Buy a headspace gauge, make one, or talk to someone that has them, in order of however you see fit. Making one, of course, requires that you know the dimensions, and are able to machine to them, whether it's with a lathe, or a grinder.
Sooo... Why do you see fit to measure the headspace in the first place?
Cheers
Trev
Cheap way to do this is to take a resized case, cut a slit with hacksaw or dremal in the neck so that you can slide a bullet in and out by hand with just a slight amount of resistence. Make sure to deburr the cut properly so it doesn't interfere with chambering the round. Push a bullet into the empty, slit case and leave it long. Chamber the round and remove carefully, you now have the distance to the lands.
If you leave too much neck tension on the case, the bullet will stick in the throat. Too little neck tension and you cant rely on your measurment.
While the above works fine with a little practise, a Stoney Point Gauge is the way to go.
If you leave too much neck tension on the case, the bullet will stick in the throat. Too little neck tension and you cant rely on your measurment.
While the above works fine with a little practise, a Stoney Point Gauge is the way to go.
I think there was a thread on this the other day.
Seating the bullet long and chambering is the easiest, as was said, but there was a way using a dowel as well that I'd like to try.
Yeah,here it is--
http://www.canadiangunnutz.com/forum/showthread.php?t=739228
Seating the bullet long and chambering is the easiest, as was said, but there was a way using a dowel as well that I'd like to try.
Yeah,here it is--
http://www.canadiangunnutz.com/forum/showthread.php?t=739228
In reference to the linked thread, there is a more precise way - use a brass rod, with a couple of collars, which may be locked in place with set screws.
Catch is, this sytem registers on the tip of the bullet, not the ogive. There is often variation in the distance from the critical point on the ogive to the tip. Bullets tend not to be identical when this distance is carefully measured.
The most accurate systems measure from boltface to contact point on the ogive.
Catch is, this sytem registers on the tip of the bullet, not the ogive. There is often variation in the distance from the critical point on the ogive to the tip. Bullets tend not to be identical when this distance is carefully measured.
The most accurate systems measure from boltface to contact point on the ogive.
You can steal the basic idea of the brass rod, and go with that, if you have a RC Model Airplane type hobby shop around.
K&S sells various sizes of brass steel or aluminum tubing. A piece of tubing, secured over the end of a rod (to allow the tube to register on the ogive) and a couple clamping collars (they are used a lot to hold the wheels on the landing gear. Alternate source of same thing, are drill stop collars from PA or CTire).
Cheers
Trev
K&S sells various sizes of brass steel or aluminum tubing. A piece of tubing, secured over the end of a rod (to allow the tube to register on the ogive) and a couple clamping collars (they are used a lot to hold the wheels on the landing gear. Alternate source of same thing, are drill stop collars from PA or CTire).
Cheers
Trev
This is what I did http://www.larrywillis.com/OAL.html
Easy to make and seems to work well. For me anyway
Easy to make and seems to work well. For me anyway
Hello Trev,
Could you expand on your explanation? For a 30/06 rifle as an example, the K&S tube has to be slightly less than 0.300 to slide down the barrel. The ogive of the bullet is 0.308. So the K&S tube inside i.d. has to be .308. I don't follow your brief explanation but I am very interested in understanding your method.
Thank you, I learned something today. I thought it was circle on the front of the bullet where the major diameter starts.The ogive is not the bullet diameter but the curved part of the bullet between the tip and the full diameter bearing surface. there are a lot of terms to keep track of when you a "nut".
OK, what TREVJ said above now makes sense.
I have been using the Sinclair hex bullet comparator to measure the distance of the major diameter of the bullet to the base of the cartridge. I believe this is independent of bullet nose shape and can be transferred to any other bullet shape.
If you want the most accurate measurement, the Sinclair International bullet seating depth tool, http://www.sinclairintl.com/.aspx/pid=35491/Product/Sinclair-Bullet-Seating-Depth-Tool is the most accurate that I have used. The Hornady one also works well but you need a modified case for each caliber you want to measure. http://www.sinclairintl.com/.aspx/pid=35663/Product/Hornady-Lock-N-Load-OAL-Gauge-standard- OR http://www.sinclairintl.com/.aspx/pid=35889/Product/Hornady-Lock-N-Load-OAL-Gauge-semi-auto-
Also get a bullet comparator that measures off of the bullet ogive, not the bullet tip. This is much more accurate than measuring off bullet tip as bullet tip length from ogive to bullet tip can vary significantly from one bullet to the next. http://www.sinclairintl.com/.aspx/pid=34014/Product/Sinclair-Insert-Style-Bullet-Comparator OR http://www.sinclairintl.com/.aspx/pid=34262/Product/Sinclair-Hex-Style-Bullet-Comparators OR http://www.sinclairintl.com/.aspx/p...y-LNL-Comparator-Set-22-6mm-25-270-7mm-30-cal
Hope this helps....
Also get a bullet comparator that measures off of the bullet ogive, not the bullet tip. This is much more accurate than measuring off bullet tip as bullet tip length from ogive to bullet tip can vary significantly from one bullet to the next. http://www.sinclairintl.com/.aspx/pid=34014/Product/Sinclair-Insert-Style-Bullet-Comparator OR http://www.sinclairintl.com/.aspx/pid=34262/Product/Sinclair-Hex-Style-Bullet-Comparators OR http://www.sinclairintl.com/.aspx/p...y-LNL-Comparator-Set-22-6mm-25-270-7mm-30-cal
Hope this helps....
Last edited:
Funny that.
Yeah. As long as your tube will fit down the bore, it can be used to form a tool that will rest on the ogive.
Lotsa ways to skin that particular cat. Try not to get too tied in knots over all the options. Load and shoot, and when you are pretty sure you can shoot better than the ammo and rifle are, then start working on all the variables.
Get a kinetic bullet puller. Thats the hammer type.
You can load a bullet into a case with no primer, mark the bullet with a Sharpie or similar marker, and chamber it, look at the marks on the ogive, from the rifling.
You can use this method to figure out at roughly what length you get contact. After that, you start trying to figure out whether more, or less, is what works better.
But, like I said. Load and shoot. Enjoy yourself. It's not supposed to feel like Algebra homework.
Cheers
Trev
What is your definition of ogive?
Huntsman LXXII
New member
- Location
- Edmonton AB
Thanks for the info, these posts really help a new reloader understand the variables that affect optimizing a load.
You should maybe do some looking into that.
My definition of ogive is more like hunter5425's.
The point where it reaches bore diameter? Really? That's where the ogive ends. Or begins. Depending which end you started at.
But the whole curved section, is the ogive.The comparator tools are carefully made, so as to be able to measure the same location on that curve, from bullet to bullet from the same batch of bullets made to the same shape. Supposedly.
I'd trust them, if I had sprung for hand made bullets, that were all swaged in the same die set, but if you are comparing bullets that may well have been puked into the bin by a battery of dies (ie: factory made bullets), you are reliant upon the wear and the consistency of the shapes of several swage dies all of which can be counted on to be at least a little different, by the time they are reamed and lapped out.
Far better to measure off a nearly consistent point on the ogive, than to try to measure off the tip of the bullet, but not perfection. And only as good as the bullets being measured.
's OK though. Perfect never happens.
http://www.accurateshooter.com/ballistics/tangent-vs-secant-vs-hybrid-ogive-bullets/ Worth a read.
Cheers
Trev
Definition of ogive: pronounced O-jive, Almost all ogives are circular arcs. The circular arc will either be TANGENT to the bearing surface or SECANT to the bearing surface. If the arc joins the bearing surface smoothly, it's called a TANGENT ogive. If there is a visible, abrupt junction between the bearing surface and ogive, then it is a secant ogive. Some examples of TANGENT are, sierra matchkings, nosler ballistic tip and berger BT. SECANT examples would be the berger VLD, hornady A and V max, and some lapua scenars.
The ogive of a bullet is usually characterized by the length of its radius.
The ogive of a bullet is usually characterized by the length of its radius.
You should maybe do some looking into that.
My definition of ogive is more like hunter5425's.
The point where it reaches bore diameter? Really? That's where the ogive ends. Or begins. Depending which end you started at.
The comparator tools are carefully made, so as to be able to measure the same location on that curve, from bullet to bullet from the same batch of bullets made to the same shape. Supposedly.
I'd trust them, if I had sprung for hand made bullets, that were all swaged in the same die set, but if you are comparing bullets that may well have been puked into the bin by a battery of dies (ie: factory made bullets), you are reliant upon the wear and the consistency of the shapes of several swage dies all of which can be counted on to be at least a little different, by the time they are reamed and lapped out.
Far better to measure off a nearly consistent point on the ogive, than to try to measure off the tip of the bullet, but not perfection. And only as good as the bullets being measured.
's OK though. Perfect never happens.
http://www.accurateshooter.com/ballistics/tangent-vs-secant-vs-hybrid-ogive-bullets/ Worth a read.
Cheers
Trev
Im sorry Trevj, What you said is correct and IS what I was trying to get accross to everyone. I guess I was assuming that most reloaders know how a comparator works and that it measures off of a diameter slightly smaller than bullet diameter on the curved ogive of the bullet and is more accurate than measuring off of bullet tip even though not all bullets are identical due to manufacturing variances, it is much more consistant than measuring cartridge overall length off of bullet tip.
Cheers and happy reloading..............Big grizz
