9mm short throat... confused...

[Schony]

So I am just getting started reloading for my BHP and the throat is very short. I need a OAL of 1.027 for them to not be hitting the rifling. I am using a lee 356-125-2R mold and will be using unique powder. I am very worried about using a OAL this short. Should I just make them long enough where they chamber and not worry about hitting the rifling or should I just use a really low powder charge and run them short? Going to the range this weekend and would really like to do some testing with the HP. Any help is really appreaciated!

[beagle]

The throats on most 9mm are almost non-existant. Most are made to accept a .356" jacketed bullet and that's it. Not cast friendly at all.

I always though a 9mm was a *** cast gun until I shot with a fellow that used a S & W M39 and he consistently shot 2" groups offhand at 25 yards with cast. After watching him one summer, I decided that I had to try and see what I was missing. Now, I have four 9mms.

The best solution I have found is to take about a .357" bullet and seat it deep enough to feed and chamber and reduce the powder charge accordingly so as to not create excess pressure.

Eventually, you'll find the magic combination and then watching for pressure signs, you can up the load a little while maintaining your OAL. It's usually pretty easy to find a load that will clock over 1,000 FPS and shot and feed well.

The Ruger Blackhawk convertibles are even nastier to play with as my two have no chamber throat at all. If I use .358" bullets or bigger in them, I get small rings of lead in front of the case and this ties up chambering. At .357" and seated to chamber with a taper crimp, they do all right.

At present, Wally is fighting this battle. But, all of us hate to waste this nice 9mm brass just begging to be picked up on the range and the 9mm makes a nice little plinker so it's worth the effort./beagle

[ku4hx]

So I am just getting started reloading for my BHP and the throat is very short. I need a OAL of 1.027 for them to not be hitting the rifling. I am using a lee 356-125-2R mold and will be using unique powder. I am very worried about using a OAL this short. Should I just make them long enough where they chamber and not worry about hitting the rifling or should I just use a really low powder charge and run them short? Going to the range this weekend and would really like to do some testing with the HP. Any help is really appreaciated!

Using Lee's truncated cone and round nose boolits I load to a cartridge overall length of 1.125"-1.130". I've loaded and shot thousands in my BHP and Glock 26, 19, and 17.

Once I get the OAL and neck diameter right, functioning is essentially flawless.

If an OAL of longer than 1.027" causes the boolit to impinge on the rifling, I'd say you need a different profile boolit. Possibly a truncate cone.

[MtGun44]

The TC may allow longer seating if you want, because it has a shorter full diameter section
before the taper starts.

You don't have to get too carried away with the reduced powder charge. If you are
moving the base into the case more, you want to reduce the charge a bit, but you should
not be reducing the velocity. Use your chrono and you can bring the charge back up to get
the 'rated' book velocity with that powder under that wt boolit. Please note the length
of the test barrel and reduce your expectations based on your barrel length, which is
often shorter.

You DO want to reduce powder charge when you reduce combustion chamber volume, but
you so this to keep the pressure the same. Therefore, the velocity should be the same.
This is where the chrono comes in.

Bill

[MakeMineA10mm]

Bill nailed it! I have a Walther P88c that has an extremely abrupt and sharp throat. It won't allow the slide to close on most commercial (factory-loaded) JHPs, and wouldn't work with any of my 9mm boolit moulds except a Saeco spire point RN and the Lyman 356402, which is a long, narrow, tapered TC. The noses on those two designs didn't hit the throat... I'd recommend trying them, as the standard loading data works fine with them in this situation...

[Cherokee]

Lyman 356402 & Lee 356120TC work great in my 9mm's.

[oldandslow]

schony, 3/11/12

Congratulations, you have the exact same problem that I had with the Lee 356-125-2R mold. I've loaded about 40,000 9mm FMJ's without any problem in my 9mm's but could not get the Lee 356-125-2R to chamber in any of my 9mm pistols without loading them much shorter than I had before. This is after sizing the bullets with my Lyman 4500 lubrisizer. Unsized bullets were even worse (mine drops unsized bullets from 0.357-0.358"). In comparing the lead Lee bullets to the FMJ's that my pistols love the Lee ogive is quite a bit fatter than the FMJ's which means that it must be loaded shorter so the ogive does not hit the lands.

My solution was to buy another mold with a thinner ogive. The one I settled on was Tom's Accurate Mold, 9mm, 135 grain, five bullet mold in Aluminum machined to drop 0.357" bullets. It drops unsized bullets at 0.3575-0.358" and they work fine loaded as cast (that is, unsized).

The good news is that the unsized 9mm Lee bullets with the fat ogive work perfectly in my 38 special SW revolvers. So at least I found a use for the non-working 9mm mold. Good luck and don't get too frustrated. The good folks here have helped me through a lot of hair-pulling hard times.

best wishes- oldandslow

[cwheel]

I'm a little confused here. Why wouldn't you just use a throating reamer, none of these adjustments would be necessary. Common thing when loading auto pistol rounds with cast that the bullet hits the rifleing before the case can headspace on the case mouth. You are able to cut the throat to whatever you need, and the Clymer reamers are cheap. My 45 acp pistols have to be slightly throated to use the two styles of the bullets I cast, so I just run the throating reamer in a little during the build and never a problem. Might have something to do with the design of the bullet you are casting. My old BHP and Ruger P89 both run fine when casting Lyman 358242 round nose without any special effort. I was never comfortable running a bullet into the case deeper, it decreases the volume of the case and takes you off scale on the reloading charts. Sure, you can work up loads again, but why if unnecessary ??
Could be I'm missing something here ??
Chris

[MakeMineA10mm]

Couple things, I can think of Chris:

1) A lot of people are uncomfortable doing this sort of work, even though it is relatively safe/low-risk. (At least if you go very slow and keep checking your work frequently.)

2) I was worried about messing with the throating on my Walther, because it is the most-accurate pistol I own. It will regularly hold 1" groups or better at 25 yards, with slow, bench-rested fire, and standing on my two hind feet, it will shoot about half the size of the 10-ring of the B27 silhouette, which is to say all the bullet holes are well inside the X-ring. I don't want to find out the throating had something to do with that, after the throat has been cut away...

3) While deeper-seating is a pain and causes one to re-make their ammo entirely for that particular pistol (something I heartily agree with you on -- it's not optimal at all), it does teach one the importance of working up (or down) loads, no matter what the change. We should be doing this whenever we change any component, even by lot number.

Now, in the grand scheme of things, I like having one standard load for a particular caliber that works in everything. (Kind of like my own version of Winchester White Box, but generally with lead boolit loads.) What I resorted to was identifying a boolit in 9mm that worked in everything. (That Saeco #115 I mentioned in my prior post -- which is more spire-pointed than the line drawing on Saeco's website. I don't know if they've changed the design or if it's just a bad drawing?) I added some weight so I could load subsonic or supersonic, and it's a weight that seems to work ideally in 9mm. I ran a mould group buy for it, and now that's my standard boolit for my standard load, and it works in even the short-throated Walther. The spire-point also makes it a terrific feeder in even picky feeding pistols.

So, my work-around was the bullet mould, instead of the throat reaming. One of these days, if I get brave, I might try reaming that throat, because it is annoying that it doesn't feed factory jacketed ammo (esp. HPs), but for now, for 99% of my shooting, I'm good with that pistol even with the short throat, but you are right - reaming the throat is a good solution.

[MtGun44]

I'd much rather adjust my ammo to match the gun than ream the barrel. I also worry that the
reaming risks damaging the barrel. Choosing a TC boolit is pretty easy and it works in all
of my different 9mm, a pretty good slice of the ones out there.

Bill

[Schony]

went out shooting today loaded some from 3.7 to 4.5 with unique. Had some pretty decent groups but also had some that wouldn't feed all the way... I am going to try a different mold probably going to go with lee 356120TC I really don't like how far I need to seat the bullets. Would rather try a different bullet b4 I start worrying about reaming throat. Kind of a bummer but that's the way it goes. Thanks everyone for the great help I really appreciate it!

[Harter66]

Schony,
I shoot an BHP clone.

WIN brass .
CCI 200(?SPP)
3.8 Unique
LEE 356-124 TLTC as cast .359/127gr WDWW
Lubed w/mod. Darrs. 12oz vasoline/16 oz parofine/3 tsb STP.
1075-1110 fps next to noleading
Don't know the oal off hand seated down until the "driving band"is just even w/the case mouth.
Shoots 3" 30yd groups up to 250 rounds or so w/no cleaning.

[cwheel]

Before I started throating 45 acp barrels, did an experament on a 70 series colt. Before and after groups fired from a rest weren't any different. Have not done this to any of my 9's yet, they havn't needed it. BHP, P89, Kel-Tec PF9 the Lyman 358242 works with all. Throating takes away just a little of the rifleing at the headspace step and will let the pistol chamber and fire almost any round. Headspace is located at the OD of this cut, not the ID. Often from the factory this space in the chamber has a square sholder. With a short chamber it makes it even more important to do this mod to feed ammo other than hard ball. It takes longer to strip down the gun than to make the cut. I think everyone needs to take the time to work up your loads, what ever you reload. But being off the chart to start with makes this a longer task. Guess everyone deals with issues differently, speaking for myself, I like to maintain the
OAL of the round.
Chris

[Bullet Caster]

Well, my dos centavos, is that after reloading my 9mm, I drop 'em each and every one down in my chamber with the slide locked back. If they chamber they go into the "shoot" pile. If not they go into the "reject" pile and pulled down and checked. That's my QC. BC

[MakeMineA10mm]

Before I started throating 45 acp barrels, did an experament on a 70 series colt. Before and after groups fired from a rest weren't any different. Have not done this to any of my 9's yet, they havn't needed it. BHP, P89, Kel-Tec PF9 the Lyman 358242 works with all. Throating takes away just a little of the rifleing at the headspace step and will let the pistol chamber and fire almost any round. Headspace is located at the OD of this cut, not the ID. Often from the factory this space in the chamber has a square sholder. With a short chamber it makes it even more important to do this mod to feed ammo other than hard ball. It takes longer to strip down the gun than to make the cut. I think everyone needs to take the time to work up your loads, what ever you reload. But being off the chart to start with makes this a longer task. Guess everyone deals with issues differently, speaking for myself, I like to maintain the
OAL of the round.
Chris

That's good info. Very reassuring. I can't imagine 9mm barrels being that different than 45 barrels, at least from the issue at hand. I may get brave and try the finish ream on the Walther after all...