I have read that an accurate method for determining a rifle's cartridge length is to drop a specific bullet into the throat of a gun and while supporting it, run a cleaning rod in the muzzle until it contacts the bullet and mark the rod. Then remove the bullet, insert and close the bolt (cocked), re-insert rod and mark again. The proper length for that bullet in that gun should be the distance between the 2 marks on the rod.
I performed this on my Rem 788 in 22-250 and came up with a length of 2.520" with a 55g spitzer bullet. This seems too long given that my Speer reloading manual lists a COL of 2.350" for this bullet/caliber combination.
Is it possible for my rifle's length to be .17" longer than Speer's stated COL?
Is my method to determine the cartridge inaccurate or flawed?
Any help appreciated.

Thanks in advance
Mark

I'm by no means an expert but what I did was put a bullet in a case and slowly seat it deeper till it would chamber. I came up with 2.470 in my Ruger #1 (22-250). I also read somewhere here that relatively short frangible bullets like your 55 and my 50 do better seated to full depth because (1) seating it out leaves you with so little bullet in the neck that you end up with a lot of runout and (2) fragile bullets tend to deform some on initial movement when they don't have the full support of the case neck. Both are bad for accuracy. I just seated all mine to 2.350.

I'm sure there are folk here with much much more experience that'll have more to add (and maybe some will call BS on me )

Ruger#1:
What kind of accuracy did you see when you seated at 2.350 vs the longer seating?
Thanks
Mark

I dunno just yet, I just started reloading bottleneck cartridges myself, have only put about 10 of my reloads downrange, and those were just informal shooting at fun targets (pudding cups at 100 yards). Those 10 did shoot 100% better than white box Winchester 45gr HPs tho, I couldn't keep those in a 5" group to save my neck. With my loads, a quick scope adjustent and I was plastering those cups with every squeeze of the trigger. I suppose they are about a 1.5" circle they way I had them laying down with the top facing me. I have 40 loaded up and plan on some serious group shooting the first nice day I get at the range.

My reply was just quoting what I have read in the past couple months, no personal experience either way. I expect someone with better info will speak up tonight when folks stateside get online.

MDH1053: I use an inexpensive (and short - about 14" long) tool by Sinclair that Brownels sold some time back. It uses a similar method of measurement. It has helped cut my load development time and effort down to minimal! This inexpensive tool has paid for itself in the last 7 years or so many times over in savings of bullets, powder and primers.
The tool measures the distance from a stop placed in the bolt less action to the base of an intended to be handloaded bullet that has been dropped into the rifling of the barrel. The bullet is tapped out of the rifling and an empty case is placed in the chamber tapped home and the tool is inserted in the action and measurements are then easily figurable from the base of the empty brass in the chamber to the base of the bullet that was in the rifling. You then make up a cartridge with the ogive of the bullet just 2 or 3 thousandths off of the Rifling. No guesswork for feel or fit or camming power of the bolt. An exact measurement for C.O.A.L. and jump to the leades of the rifling is quickly available every time. This also works on Ruger #1's.
I see no reason why your method would not work also. There are believe it or not Rifles with incredibly long throats and extra long C.O.A.L.'s are needed to be just off of the leades of the rifling. Often times the cartridges so made or adjusted will not work through the magazine or the bullet has to little of itself inserted in the case neck to be stable in the case. Ruger #1's for many years in the 1980's had this long throat problem especially in their 257 Roberts cartridges. The .170" excess you are measuring is entirely possible. What kind of Rifle do you have and does it have a magazine? How much of the bullet is below the case mouth of that loaded round? Enough for it to be stable in transportaion cartons or cases?
More later dinner bell here!
Hold into the wind
VarmintGuy

StoneyPoint OAL gauge.

muck

IMHO,
The Sinclair Tool is the way to go. Similar to the Stoney Point System, however, it is better in two ways. Firstly, it uses a fire formed case from your rifle's chamber which makes it's measurements more accurate than a generic case made to SAAMI spec. Secondly, you don't have to buy a tapped casing from SP for each new chambering. The cat's ass if I do say so myself...

Regards, Matt.

www.sinclairintl.com

[ 04-11-2003, 09:32: Message edited by: Matt in Virginia ]

MDH, I haven't used the Sinclair tool, but I do use the Stoney Point gauge. It works quite well and I would recommend it. Your method works to a certain degree. When you get into measuring thousandths of an inch, where you measure your mark on the rod each time can be quite different. It all depends on how accurate you want to get with your measurements and your loads. If you plan on trying to shoot half and quarter inch groups, I would say get a guage. If you are happy with the inch or inch and a half groups, your method is fine.
Also, don't worry about exceeding the OAL listed in your loading manual. That number they give is simply a standard which ensures ammo of that length will fit in all 22-250 magazines. I shoot 50 grainers out of mine with an OAL of 2.490". I can only load one at a time because they won't fit in the magazine, but that's fine for varmint hunting and target shooting. The important thing is to ensure you have enough of the bullet seated in the case to hold it properly, meaning straight and secure. Mine aren't loaded very far into the case, but I can't pull them out by hand either. Hope this helps.

Just take a fired case, crimp it a little, slide in a bullet so its just in the neck, than chamber the round, it will stop the bullet on the lands, then just back it off 1/8-1/16th of an inch. And of course compare to some reloading manuals, to make sure it is safe.