Easy way to measure chamber length without fancy tools?

[mallen]

Easy way to measure chamber length without fancy tools?

[NVcurmudgeon]

Sorry

[dtknowles]

Exactly what dimension are you trying to measure? Have you consider a chamber cast or pound cast.

Tim

[mallen]

I want to measure my 9mm chamber.

[mallen]

Years ago, following instructions in a Handloader magazine, I made a brass rod that fit into the mouth of a fired case. It had two diameters; one to fit into the neck of the case not too tight, and the other SLIGHTLY larger and not very long to stop the movement of the homemade tool when fully chambered. It worked very well, just what the doctor ordered to keep me from over-trimming my .303 cases in a No. 4 rifle. I made this tool using a vise, quarter inch drill, and a file. Measuring the case with the gauge is easily done with a caliper.
There is a letter by me on the .303 Page in their handloading section. Some rifles are made with very long chambers, and others with very short chambers!

[calgunner]

I don't if this will work for pistols but it what I use for rifles. This is the link "www.gun-shots.net/wp-content/uploads/measuringoveralllength.pdf".

[dromia]

NOE Chamber length buttons?

http://noebulletmolds.com/NV/index.php?cPath=90

[dtknowles]

I want to measure my 9mm chamber.

I think you could try using a piece of .223 brass cut if off so that it will almost chamber (leave it a little long) expand the mouth and push it into the chamber. Since it was deliberately too long it won't go far enough, right. Now trim a little off and try again, hopefully it won't go this time either but measure the length and record. Trim a little more and repeat until you get it to chamber. Now you know the chamber length is between that last two measurements. If you want a more precise measurement, start with a new case and your next to last measurement an go slower.

Tim

[Blackwater]

dtknowles nailed it. The cheapest/best way to do it without any fancy dancy stuff that'll just cost you money unnecessarily. You can do it with bottleneck rounds, too by simply taking cases that the book says need trimming, and trying them in your chamber. When you find one that causes the bolt to close with some "feel" and resistance, trim it a tiny bit, try it again, and when it closes with the gentlest of "feel," subtrace a couple of thousandths or three, and that's YOUR rifle's max. cartridge case OAL.

To find the maximum OAL for loaded rounds, where the bullet's ogive just kisses the rifling, do it the same way - load overlong and see if it'll chamber. Then keep moving it back a touch, maybe 1/8 to 1/16 turn of the seating stem, and retry until the bolt closes with a minimum of additional effort, and that's your OAL with that bullet. Though some target shooters find that bullets seated a little longer, and solidly in hard contact with the lands, this isn't a good idea if you'll be using the loads for hunting or defense because if you do that, and the bullet sticks in the rifling, when you try to extract the ctg. it can pull the bullet right out of the case and spill powder down into the action, which will most likely necessitate your having to take the barreled action out of the stock to completely clear it all out - not a pleasant task.

One other thing that I seldom see mentioned today, but that goes along these same lines, is when you're setting your resizing die for YOUR gun, if you take a fired case and leave the bottom of the die about 1/16" or so above the shell holder, and run the case through, you'll probably find it doesn't want to chamber because as the case is resized, it's also lengthened. That brass that's moved has to have somewhere to go, so it oozes forward, and this is what causes the case to not want to chamber. Then, you simply screw the sizer die down and try again, and again, going 1/8 turn or so at the time, until the case chambers with just a slight "feel." This is how you fit your die to YOUR rifle's chamber. When you do this, the angle of the bottleneck slides the case upward, off the bottom of the chamber, and centers it with the bore. This often produces a bit better accuracy, particularly when you also fit the bullet to the lands (IF that OAL isn't too long for your magazine, which is always yet another consideration as well). This puts everything - the case and bullet - in better alignment with the center of the bore, and having them thus better and more completely centered can and does affect accuracy very positively. These are old "tricks" that I never see mentioned any more. That last one certainly produces longer case life by limiting the amount the case CAN stretch. I've shot some '06 and .270 cases 40 or more times with complete satisfaction and no losses, adding in only neck annealing a time or two along the way when a neck cracked from hardening, but even that seems to be minimized, though not eliminated completely. Just be sure if you're cobbling hunting or defense loads together that they flow through the action with a minimum of "feel" so that any follow up shots you might sometime need to make are reliable. Reliability HAS to be the final factor in this, but even then, getting as close to fully fitting your sizer die for your chamber helps significantly, even when you hedge your bets slightly for reliability's sake.

Oh yeah! Almost forgot. The only problem with this is when you have multiple guns in a single caliber, and want to use the ammo in any or all of them. This means that you'll have to set your die for the shortest chamber and throat lengths or the ammo won't fit them all. If you've got a pparticular rifle for accuracy, it's a help to have a die set that you can adjust specifically for THAT rifle if you're seeking the ultimate accuracy achievable with it. Hope this makes sense.

[SwedeNelson]

Here's the quick and easy
http://noebulletmolds.com/smf/index....pic,440.0.html

Bullet maker, maker
Swede Nelson

[fa38]

dtknowles nailed it. The cheapest/best way to do it without any fancy dancy stuff that'll just cost you money unnecessarily. You can do it with bottleneck rounds, too by simply taking cases that the book says need trimming, and trying them in your chamber. When you find one that causes the bolt to close with some "feel" and resistance, trim it a tiny bit, try it again, and when it closes with the gentlest of "feel," subtrace a couple of thousandths or three, and that's YOUR rifle's max. cartridge case OAL.

I have also found that if you remove the firing pin, spring and sear assembly on a bolt action you get a much better feel for a resistance to closing the bolt on a case that is a bit too long and that needs to be trimmed more.

[mallen]

well. by using the die to seat the bullet little bitty bits at a time i was able to get a plunk test to work at 1.185. unfortunately, the round would hang on the mag. i had to back down to 1.18 to get it to cycle. that was after a few presses and loading, so the corners of the bullet are slightly beveled. i might be able to keep the same length by polishing the inside of the mag where it kinda bevels in at the top.
any way of doing this?

[country gent]

Are you rying to measure chamber length ( length of the actuall case head to mouth) or are you trying to measure Overal cartridge length? They are diffrent measurements. If its overal length ( OAL) then you might try loading just a few and testing single loading to see if accuracy is improved before modifing on mags or firearm. "Polishing" a mag out any real amount weakens it. Most mags are barley .060 thick materials and vary greatly in actual hardness. Any more than removing burrs or a light polish to smooth surfaces may create other issues. Taking .008-.010 out dosnt sound like alot but its a fair amount when stock is that thin to start with. If you absoultly must do this then disassemble the mag completely removing base spring and follower. Make note of front of spring as some are specific to work correctly. Then with a very fine jewelers file and gentle strokes rework the surface to what you want. For a finer polish use a piece of brass with very fine polishing compound. Be prepared though as weaking the mag may make replacing it nessecary.

[fouronesix]

Well the "plunk test" should tell you the round will fully chamber and headspace on the mouth. I would check the case lengths. The standard trim length for the 9mm is .751". They need to be very close to that. The case length is the headspace control for this cartridge.

The 9mm cartridge OAL should be no more than 1.169". If the bullet is designed for the 9mm- any reason you can't seat the bullet to result in a cartridge OAL of 1.169"? The mag should already be sized to handle the 1.169 cartridge OAL.

[mallen]

Chuckles. my dummy rounds are at 1.180. little longer than saami. but they are .005 away from the lands.

but, im being told that getting closer to the lands will make no difference at all.

my other option do to the bullet shape, is really really really much shorter. 1.09

[fouronesix]

Well, the whole ball game with reloading semi auto handgun ammo is function and safety. Semi auto handgun ammo like the 9mm are best crimped only with something like a taper crimp so I don't know why there would be only two length options….. unless the crimp groove is in the wrong place and you are trying to use the crimp groove. The taper crimp is used because the round is headspaced on the case mouth when chambered. Loading so the bullet engages the rifling (or comes close) as a primary concern, can be counterproductive to the two critical elements of function and safety.

Just for consideration.
Here's a couple pics of 124 gr JHP 9mm Speer factory- a very reliable, safe, powerful and effective cartridge in the 9mm semi-auto handgun.

Note the cartridge OAL 1.125 and note the lack of visible crimp and no crimp groove.

[9.3X62AL]

This is among the more uncouth reactions to a good-faith response for information I have seen on this site during my 18 years of membership. Your inability to visualize from text is not the poster's responsibility.

[mallen]

This is among the more uncouth reactions to a good-faith response for information I have seen on this site during my 18 years of membership. Your inability to visualize from text is not the poster's responsibility.

wow. you sure read a lot into that one.

ill take your comment as admission that you enjoyed the image.

i did not make it however.

[BruceB]

I did not make it however.

No, but you used it.

I note your date of joining this website.... September this year.

With barely three months' membership, perhaps you've not noticed that we (most of us) try to maintain some semblance of civility in our dealings with other members. The comment about "no pictures/didn't happen" has been used frequently without undue disruption.

However, I too find the graphic to be insulting and excessive. It's not funny.

Remember, there is no way to tell, on an Internet board, exactly what a poster's precise intent may have been. It takes considerable care to ensure that the meaning isn't lost due to misunderstandings.

I don't think you meant this in the manner it comes across; at least, I hope not. NVC established his credentials long ago and his words MEAN SOMETHING. It behooves all of us to at least seriously consider his input, because he knows what he's doing.

[mallen]

Remember, there is no way to tell, on an Internet board, exactly what a poster's precise intent may have been. It takes considerable care to ensure that the meaning isn't lost due to misunderstandings.

so i think ill just make an assumption that its insulting, even tho there is absolutely no context to suggest such.

..........