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poppy42
07-30-2017, 06:01 PM
Here's my problem I got a new mold I'm trying out for my 9mm. I have been using a Lee, 124 grn round nose bullet. My new mold is a Lee, 124 grn tc bullet. My question is I can't find a listing for the new bullet in any reloading manual and I am concerned about the oal. The RN bullet lists the oal as 1.125 the new bullet is a couple thousands shorter (.605 as opposed to.585 +-) do I adjust my oal accordingly or keep it at 1.125.
Be kind to the newness. Any help would be greatly appreciated
Thanks

rod.t.stuart
07-30-2017, 06:11 PM
Here's my problem I got a new mold I'm trying out for my 9mm. I have been using a Lee, 124 grn round nose bullet. My new mold is a Lee, 124 grn tc bullet. My question is I can't find a listing for the new bullet in any reloading manual and I am concerned about the oal. The RN bullet lists the oal as 1.125 the new bullet is a couple thousands shorter (.605 as opposed to.585 +-) do I adjust my oal accordingly or keep it at 1.125.
Be kind to the newness. Any help would be greatly appreciated
ThanksI would start by measuring the overall length of the bullet compare between the two then subtract off how much the truncated bullet now make that your overall length by subtracting it off what you used to load your round those bullets to example if you're loading to 1.130 and there's a difference of well let's just make it easy numbers of .030 then your new overall length would be 1.1

Sent from my SM-G930V using Tapatalk

Dusty Bannister
07-30-2017, 06:12 PM
Cleaning rod/dowel method of finding cartridge OAL

This is what I use for my guns to determine the max OAL and this eliminates any question of the crimp, incorrect case prep, or other operator induced error.

This method works well on rifles and single shot pistols as well as Semi-autos. You can use a flat tipped cleaning rod, or flat tipped dowel rod. You will also need a sharp pointed pencil, a short dowel and a bullet sized but clean, of the type you are going to load.

For Rifles
Make sure the chamber is empty. Close the bolt, and be sure the firing pin is retracted into the bolt. Insert the dowel or cleaning rod and hold it against the face of the bolt. Mark the rod at the face of the muzzle. Remove rod, open bolt and remove it from the action. Insert the bullet into the breech and hold it snug into the rifling. While in that position insert the dowel or rod again, and with it firm against the nose of the bullet, mark the rod at the face of the muzzle.

The distance between the center of those two marks is the max cartridge OAL for that rifle, with that bullet sized to that diameter.

For Semi-autos
Remove the barrel from the slide and make sure it is clean and free of leading or other debris in the barrel and chamber. The dowel or cleaning rod needs to be longer than the barrel. Hold the barrel, muzzle up, and place the barrel hood on a flat surface like a table top. Insert the dowel or rod from the muzzle and mark the rod exactly flush with the muzzle. Remove the rod and insert the bullet you intend to use into the chamber and lightly press and hold it in place with the short dowel. Place the assy muzzle up on the flat surface. Insert the rod/dowel into the muzzle so it rests on the nose of the bullet and again mark the rod exactly flush with the muzzle. Remove and set the barrel aside. The distance on the center of the two lines is the cartridge OAL. Seat a dummy round to this length, or slightly shorter and begin to apply the taper crimp until the dummy passes the plunk test. This is the optomim cartridge OAL length for this bullet in this gun.

You may need to adjust the seater to shorten the OAL if this does not feed from the magazine, but generally this will be a great fit. Remember, if you seat and crimp in one step, you might force a slight ridge ahead of the case mouth and that will screw up your seating.
Dusty

country gent
07-30-2017, 06:17 PM
I use the cleaning rod tape method a lot on some rounds I sacrifice a case by putting a couple slits in the mouth back ( a collet then) depurring and then sizing so a bullet is held tight and snug but can slide. Insert bullet into this case long and chamber easily and carefully. Remove and carefully measure length. Rifling should seat deeper into case and collet should hold it.

poppy42
07-30-2017, 06:33 PM
Thanks guys.

Bama
07-30-2017, 06:47 PM
Listen to Dusty

popper
07-30-2017, 06:58 PM
Pull the barrel and make some dummys of various COAL. See what fits (longest) then drop back maybe 0.01". Make some that COAL, load in mag and see what feeds. COAL is feed and function first for auto loaders. Then see how much powder space you have and load low to start. COAL is suggested start for the TEST barrel/powder & boolit. You're not changing weight so starting book load should be good, powder wise.

Scharfschuetze
07-30-2017, 09:13 PM
OAL needs to be a compromise. The length has to be such that it feeds from your 9mm magazine (neither too short or too long), yet the ogive can't be intrusive into the throat of your barrel.

I don't know which 9mm you have, but just load to a length that allows you to load your magazine without the round hanging up. Take those cartridges and do the old "Ker Plunk" test. If they drop into your chamber with a ker plunk, and they feed from the magazine, you're good to go. If they don't, reduce the length until they do and then perform a function check.

Once you figure it out, the load should work in most 9mm pistols that have a standard (isn't that a joke) chamber.

runfiverun
07-31-2017, 12:28 AM
I do it pretty much like Scharf.
I start long and come back then function test [decide on my load based on that] then load a few and try them.

Ricochet
07-31-2017, 02:37 PM
The cleaning rod or dowel method is the way to determine the max OAL that a boolit can be seated touching the origin of the rifling. Through experience I can tell you that loads for the Lee 9mm round nose and TC boolits don't simply exchange straight across, though. Loads listed as safe maximums with the round nose are very hot in all of my 9s with the truncated cone boolit, requiring substantial reduction. Look at the outlines of the boolits. More of the metal is in the rounded nose of the RN, and is outside of the case. The nose of the TC is skinnier. More of the boolit volume is seated inside the case at equivalent OAL. In many larger cartridges that wouldn't be significant, but in the little 9mm Luger with its relatively dense loadings and high pressures it can and will bump pressures too high.

Flashman929
07-31-2017, 08:25 PM
Size a case.
Cut a thin slit through both sides, like with a dremel tool.
Seat a bullet.
Chamber the round.
Extract and measure.
Repeat a few times to ensure accuracy.

This will give you the max length to your lands, aka max COAL. Play with it from there for feeding, etc. 5 thou off the lands would be a good place to start to ensure reliable chambering. More jump is just fine, and deeper seating will increase your load density. Too much jump in a rifle can detract from accuracy, but that's not important in a pistol.

COAL is an *ok* measurement, but what it's standing in for and what really matters is length from base to ogive. Sets of gauges to attach to your calipers that fit on the ogive are cheap and very useful. Mind you, not really important for pistol loading, you'll get away fine with using COAL base to nose.

rintinglen
08-01-2017, 05:29 AM
+1 to Richochet's cogent advice.
Different boolit designs have different lengths in ways that matter. The wise old admonition to start low and work up especially applies here in the 9 mm.

EMC45
08-01-2017, 02:53 PM
I was gonna say what Scharfschuetze said, but he beat me to it.

Make sure they fit in magazine. Make sure they pass "plunk test".

fredj338
08-01-2017, 02:57 PM
Pull the barrel and make some dummys of various COAL. See what fits (longest) then drop back maybe 0.01". Make some that COAL, load in mag and see what feeds. COAL is feed and function first for auto loaders. Then see how much powder space you have and load low to start. COAL is suggested start for the TEST barrel/powder & boolit. You're not changing weight so starting book load should be good, powder wise.

^^THIS^^^ OAL is probably the single most misunderstood part of reloading. IT is ALWAYS bullet & gun specific, regardless of what any data tells you. The loaded round MUST fit your gun, so it is trial & error for every gun, every bullet style. Bullets are rarely plug & play.

reddog81
08-01-2017, 03:20 PM
^^THIS^^^ OAL is probably the single most misunderstood part of reloading. IT is ALWAYS bullet & gun specific, regardless of what any data tells you. The loaded round MUST fit your gun, so it is trial & error for every gun, every bullet style. Bullets are rarely plug & play.

I agree with the above post but would like to add that you must test for function in the magazine also. There are times when I have determined a good OAL - It feeds from the magazine and chambers OK, but when you fill the magazine full of rounds the nose get hung up and jams the magazine up. My newer Delta Elite and an old Colt 1903 Hammerless are the first guns that come to mind regarding this problem.

Scharfschuetze
08-01-2017, 03:38 PM
I agree with the above post but would like to add that you must test for function in the magazine also. There are times when I have determined a good OAL - It feeds from the magazine and chambers OK, but when you fill the magazine full of rounds the nose get hung up and jams the magazine up. My newer Delta Elite and an old Colt 1903 Hammerless are the first guns that come to mind regarding this problem.

That's my experience too and why I say that OAL is really a compromise in magazine fed rifles or pistols. It's got to function before it's usable in the weapon. While touching the lead with the ogive may be advantages in a rifle, most 9mm handguns will never know the difference if the bullet is a ways back from the lead or throat.

It's interesting that a few rounds chambered by the big manufacturers in rifles, were put into the wrong action and could not take advantage of case volume and the ability to get the bullet out to the rifling. One round that come to mind is the 6mm Remington. A couple of manufacturers chambered their short action rifles for the rounds, but used a long lead in the chamber. If you wanted to load from the magazine, you could never get the bullet out to the lead where many of these rifles shot best.

DocSavage
08-01-2017, 06:50 PM
Plunk test then load in magazine to make sure fit and feed. Of my 9 mm pistols only my CZ 75 requires that I seat the bullet to suggested oal.

308Jeff
08-01-2017, 07:18 PM
Cleaning rod/dowel method of finding cartridge OAL

This is what I use for my guns to determine the max OAL and this eliminates any question of the crimp, incorrect case prep, or other operator induced error.

This method works well on rifles and single shot pistols as well as Semi-autos. You can use a flat tipped cleaning rod, or flat tipped dowel rod. You will also need a sharp pointed pencil, a short dowel and a bullet sized but clean, of the type you are going to load.

For Rifles
Make sure the chamber is empty. Close the bolt, and be sure the firing pin is retracted into the bolt. Insert the dowel or cleaning rod and hold it against the face of the bolt. Mark the rod at the face of the muzzle. Remove rod, open bolt and remove it from the action. Insert the bullet into the breech and hold it snug into the rifling. While in that position insert the dowel or rod again, and with it firm against the nose of the bullet, mark the rod at the face of the muzzle.

The distance between the center of those two marks is the max cartridge OAL for that rifle, with that bullet sized to that diameter.

For Semi-autos
Remove the barrel from the slide and make sure it is clean and free of leading or other debris in the barrel and chamber. The dowel or cleaning rod needs to be longer than the barrel. Hold the barrel, muzzle up, and place the barrel hood on a flat surface like a table top. Insert the dowel or rod from the muzzle and mark the rod exactly flush with the muzzle. Remove the rod and insert the bullet you intend to use into the chamber and lightly press and hold it in place with the short dowel. Place the assy muzzle up on the flat surface. Insert the rod/dowel into the muzzle so it rests on the nose of the bullet and again mark the rod exactly flush with the muzzle. Remove and set the barrel aside. The distance on the center of the two lines is the cartridge OAL. Seat a dummy round to this length, or slightly shorter and begin to apply the taper crimp until the dummy passes the plunk test. This is the optomim cartridge OAL length for this bullet in this gun.

You may need to adjust the seater to shorten the OAL if this does not feed from the magazine, but generally this will be a great fit. Remember, if you seat and crimp in one step, you might force a slight ridge ahead of the case mouth and that will screw up your seating.
Dusty

Never thought of this, but it's great!

Would it be more precise using a wood dowel and then a utility knife blade laid flush with the crown to "cut" a notch in the dowel instead of using a marker? Seems like that might take several (or many) thousandths of possible error out of using a pen and eyeballing it?

Down South
08-01-2017, 07:33 PM
I didn't read all of the replies so excuse me if someone else already posted this.

I use the Plunk test. Dissemble the pistol, clean the barrel well.
Start seating the boolit and drop it into the barrel. If the boolit doesn't fit all the way into the chamber, seat it a few thousands deeper and test again, continue until the boolit casing headspaces correctly off the case mouth then run your seater die in a few more thousands and lock it down. Next, check to see if your boolit fits your magazine. If it is too long continue to seat the boolit deeper a few thousands at a time until it will fit easily into your magazine, then lock the seater die.

On edit: I forgot that some seat and crimp on one die. This works best if you crimp on the final stage with a separate die.

John Boy
08-01-2017, 07:46 PM
I can't find a listing for the new bullet in any reloading manual and I am concerned about the oal

9mm Luger has a Max OAL of 1.169. Let's say for a given bullet and load the Lee manual says a Min OAL of 1.140

Start with 1.140 and work up to determine what chambers best in your handgun

Dusty Bannister
08-01-2017, 07:54 PM
"I use the Plunk test. Dissemble the pistol, clean the barrel well.
Start seating the boolit and drop it into the barrel. If the boolit doesn't fit all the way into the chamber, seat it a few thousands deeper and test again, continue until the boolit casing headspaces correctly off the case mouth then run your seater die in a few more thousands and lock it down. Next, check to see if your boolit fits your magazine. If it is too long continue to seat the boolit deeper a few thousands at a time until it will fit easily into your magazine, then lock the seater die."
===================
Yes, that will work, but if you have a problem with the case fitting correctly, this method takes that out of the equation. The case is not used at all to get the cartridge OAL.

While a sharp knife or razor blade will also make a very fine line, some have difficulty seeing that. And if you measure from the center of the two lines, the width is not really a factor. It is an old practice, use whatever you wish. Just get er done. Dusty

Down South
08-01-2017, 08:28 PM
"I use the Plunk test. Dissemble the pistol, clean the barrel well.
Start seating the boolit and drop it into the barrel. If the boolit doesn't fit all the way into the chamber, seat it a few thousands deeper and test again, continue until the boolit casing headspaces correctly off the case mouth then run your seater die in a few more thousands and lock it down. Next, check to see if your boolit fits your magazine. If it is too long continue to seat the boolit deeper a few thousands at a time until it will fit easily into your magazine, then lock the seater die."
===================
Yes, that will work, but if you have a problem with the case fitting correctly, this method takes that out of the equation. The case is not used at all to get the cartridge OAL.

While a sharp knife or razor blade will also make a very fine line, some have difficulty seeing that. And if you measure from the center of the two lines, the width is not really a factor. It is an old practice, use whatever you wish. Just get er done. Dusty

Use a case that fits properly, BTW. I never had a problem with that once the case has went through the resizer. Of course the case needs to be trimmed to length. The OAL is determined by a case that will fit into the chamber. The seated boolit determines with the case for the correct OAL. Each pistol is different. You can build a boolit that will fit the pistol you are loading for or find the OAL listed in a manual if you want a boolit to fit any same caliber out there if listed but it might not be be custom fit for the pistol it is being fired from.
But on the other hand, I visit here rarely anymore. There are many more people here than me that exceed me in knowledge.

Strtspdlx
08-02-2017, 09:55 AM
I use dusty bannisters method. But instead of a dowel I use a dial caliper and measure like I'd be measuring depth. This way I don't have error in measuring like I could possibly get with a dowel. I also always make up a dummy round or two and make sure the plunk test and allow the slide to go fully Into battery as well as feed by hand.

blackthorn
08-02-2017, 10:43 AM
Quote "Would it be more precise using a wood dowel and then a utility knife blade laid flush with the crown to "cut" a notch in the dowel instead of using a marker? Seems like that might take several (or many) thousandths of possible error out of using a pen and eyeballing it?"

With respect to the above; when measuring for OAL, measure from the bottom of the second mark to the bottom of the first mark. Doing it this way addresses the question you raise.