Not chambering properly OR ????

[bbogue1]

For my 9mm Sig I made some 128 gr flat nosed boolits with a Lee 358-125RF mold. They have a truncated nose. Sized them to .356 and powdercoated them silver. Loaded 3.8 grains of W231 (under max) and a CCI primer. Over All Length was 1.169 (right at the max from Lymans 48th manual). Using a Lyman Checker they plunked correctly. Thgese seem to have fired just fine.

Here is the question I have. I made some Lee 356-125-2R (has a round nose) Sized to .356 and powdercoated red. 3.7 grains W231 and a CCI primer. Over All Length was 1.169 (right at the max). Using a Lyman Checker they plunked correctly. The photo shows the case has a bulge after firing. The silver bullet is what they all looked like before firing. Looks like the round failed to chamber correctly. Is 1.169 tooo long?

When I slide the round into my Sig's barrel it does not go in all the way. Since a 9mm has a tapered case is it possible the OAL is too long?



After I assemble the rounds I wipe them off with a towel and alcohol to keep them free from sticky lanolin.

[Tom W.]

Do the plunk test in your chamber, after the pistol is disassembled. You may be surprised.

[DDriller]

I think they may be too long. My OAL for 9mm is 1.125

[Cherokee]

?? If you are getting that kind of a bulge at the base and the rounds are not fully chambering, it looks like the gun is firing out of battery. I would not have thought that possible but I suggest you check the gun for defective safety. Your OAL is to long for those bullets.

[JBinMN]

I would suggest taking a sized empty case and place it in the chamber of your pistol so it is fully seated. Observe where the rim of the case sits as compared to the barrel "hood". Then take the case and expand it to fit the boolit you are using. Put the boolit in the expanded case slightly and then insert the case with the boolit in the chamber. If necessary, push the head of the case in until it matches the place where the earlier empty case head was as compared to the barrel hood. Once the case head with the boolit is the same as the first one, you are pretty close to the max. OAL of that case/boolit combo. Gently remove the case & boolit & measure the length & write it down some where for future reference for that make of firearm, caliber, case & boolit combo. ( I use a log book).

ETA: adding graphic to try to give example of "hood" & case rim comparison. ( This is a 45ACP but should be about the same I think. It is for me on my 9mm even though it is a Ruger & not a Sig.)


That is the simplest way to start checking for OAL for a certain firearm chamber, case & boolit combo I can think of. You could also use the "dowel method" to do the same & likely get an even more accurate measurement, like a "comparator". The member, Dusty Bannister, among others has explained that method many times here.

If you want to use that "dowel method", either you or I can go look for it & bring it or the link to it here. The one I offered is a "general" way to check "that particular firearm, case & boolit combo" in the simplest manner I can think of or explain.

Once you have establish the combo OAL, then you can adapt how you like, to that firearm.

I will also go down stairs & look to see where the data is for that round combo in one of my manuals. Seems to me that I just looked it up recently for someone else, but I do not memorize data, so I will have to look again.

G'Luck with whatever ya decide to do.

?? If you are getting that kind of a bulge at the base and the rounds are not fully chambering, it looks like the gun is firing out of battery. I would not have thought that possible but I suggest you check the gun for defective safety. Your OAL is to long for those bullets.

Yes, good point, I was thinking the same way about it firing out of battery, but I decided to keep things simple and try to explain how to find OAL first & then he can see about other problems once the correct OALis established.

He needs to do both, but even if he found it firing out of battery, the max. OAL should likely be known for him.

[JBinMN]

Here is one of Dusty Bannisters posts about the "Dowel method" to determine OAL:

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 optomum 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

Source: http://castboolits.gunloads.com/show...=1#post3560663

[tazman]

I use that boolit without the powder coat and sized to .357. I am using them in a Springfield Armory XDM full size pistol that has a fairly tight chamber.
The OAL I have to use for them to chamber properly is 1.023. Any longer and the nose section jams in the rifling.
If you look at the boolits after sizing, you can see where the full diameter of the side stops. That part cannot be much , if any, outside the case mouth. That is why it is necessary to seat them so short.
Used like this, they function perfectly well in my pistol and the accuracy is good.

[Taterhead]

With the "2R", my COL is SHORT or it will not chamber. At typical RN OAL, the shoulder protrudes too far, in my experience. It is a more blunt shape than others.

I can't remember the COL that I settled on at the moment, but I'm pretty sure it is a ways less less than 1.1". Probably close to tazman's length.

With your barrel in hand, work the COL down until there is a reliable kerplunk.

[mdi]

I believe Lee's "2R" bullets are "stubby" with the full diameter extending farther out, nearer the nose. So, the full caliber is extending farther away from the cartridge base and necessitates a shorter OAL. I have seen many posts about 45 ACP "2R" bullets needing to be seated deeper to "plunk"...

I use the 358-125 RF in three 9mm pistols, 3, 38 Specials and one 357 Mag, both PCed and nekkid. My 9mm OAL runs 1.160" for the three 9mms and works (plunks) quite well...

[mikwat]

I don't mean to hijack the thread, but I'm having a similar problem with my .35 Remington and .450 Bushmaster. All trimmed just below max case length, and loaded below COAL. All the .35 Remingtons chamber properly through a Wilson case gauge (still need to get one for the .450), but fail the "plunk" test. I've had no issues with commercial projectiles.

Seeing as these projectiles are the result of my first casting session ever, I'm running on the assumption that the projectiles might be the source of the issue. Both sets of projectiles are RN, Powder coated, and sized to .001" over groove diameter (slug for the .450, cast for the .35) using a Lee push through die.

Any thing else I should look into?

[DougGuy]

mikwat probably better if you start a thread.

[DougGuy]

You fellas are all fighting against barrels with NO THROAT! No wonder it is such a hit and miss game to see what works and what don't. The PROPER thing to do is to have the barrel throated to add or increase freebore so you can seat out whatever COA you need to. Longer COA usually feeds much better.

SAAMI specs call for freebore seems like none of the manufacturers could be bothered to adhere to SAAMI specs. Nice long freebore = less pressure due to less resistance to boolit travel, the freebore allows the boolit to exit the case, where it is held in perfect alignment centered in the bore before it engages rifling. Leading is greatly reduced or totally eliminated, accuracy is improved, feeding is improved.

There are NO negatives to having the barrel throated. Except the salt bath hardening process some mfgr's use renders the barrels so hard that only carbide will cut them and no one makes carbide throating reamers. My advice is use a good aftermarket barrel, throat it, and enjoy shooting even more when you don't have to compromise the load data, which is a secondary problem and also a poor workaround to the first problem, no throat.

These two are typical of what comes stock from the factory these days, if you have rifling running right down to the chamber, this creates a chambering problem, and is not within SAAMI specs.



Problem SOLVED. Same barrels after throating, these will now plunk and feed anything that will cycle through the magazine:

[tankgunner59]

I'm looking at my Lymans Cast Bullet Handbook 4th Edition. In the 9mm Luger listed data the longest OAL is for a 140 grain semi wad cutter at 1.160". I think you're seating the boolits a little long. The only 125 grain boolit listed is a Lyman #356637 HP at 1.010" I have had situations like this a few times and I like to get a factory round and measure the OAL for a starting point. Then I load a dummie round and plunk test it and adjust. Once I have the info I need I note it in my reloading manual. I don't have funding on fixed income to have machine or to farm out machine work. My accuracy is great with my 9mils. I've had to do the same with my wifes 380, but once it was done we had no problems at all with accuracy, feeding or leading.

[tazman]

DougGuy-----Which manufacturers are using the salt bath hardening process which is causing the difficulties?

[DougGuy]

DougGuy-----Which manufacturers are using the salt bath hardening process which is causing the difficulties?

Glock, SiG, All the poly framed Springfields, S&W M&P, there are a lot more. Melonite, Tennifer, two of the brand names of salt bath.

[Oily]

I am anal I plunck test every round that goes in my semi autos. I never have a failure to feed (FTF). When I load for my 1911 I strip my pistol and pull the barrel and plunck test every round.2000 rds and no ftf problems. Go back to the basics and you will find your problem.

[DougGuy]

I have used a Clymer reamer on 4 M&P 9 mm barrels with no problems. The reamers have been used on 5 stainless barrels since and appear to be holding up fine. I bought a M&P 357 sig barrel a few weeks back and was pleased to see a nice slow twist and a throat that was generous in both width and length. Way to go S&W.

You got lucky. Some of the salt bath hardening is similar to case hardening and once broken through the hardness layer is soft enough underneath that a HSS reamer will still cut it. Lots of the salt bath hardening goes all the way through the barrel, a.k.a. Glock, where barrels are routinely subjected to a 1500F dip that hardens them through and through. It depends on how hot, and for how long, with the hardening process.

I can think of 2-3 times where I ruined a HSS reamer, hardened rifling wipes the cut edge right off in the first 1/4 turn.