I don't shoot 9mm much any more. My son still does, so I loaded up a bunch in anticipation of his visit over the holidays. He shot my reloads over the next few weeks, and reported to me that the reloads, which were all 125gr, lead conical nose, flat point, over 4.3 gr HP-38, had uneven results.
He told me that the S&W 9-C fired all well, with good accuracy, but his new Springfield XD-m sent the rounds tumbling. He was sure that they were impacting sideways (keyholing), and the accuracy was, as expected, terrible.
The bullets were alloy, no significant leading noted. Why would the reloads have such different results?
BTW, he tells me that he has good accuracy with the Springer shooting factory ammo.

Any guesses what's going on here?

My guess would be the XD-M has a larger bore diameter, and depending on the exact bullet diameter used will stabilize or keyhole them.

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Alan
SWCA LM 2023, SWHF 220

I had similar results with some cast in a BHP. Someone told me that the bullets "skipped" over the rifling and were never stabilized. I really like to load cast, but no longer in the 9mm.

It's to bad you don't have the gun on hand to slug that barrel, it sure sounds like the rounds aren't being stabilized in the barrel.

EDIT: Without a chronograph, you don't know the velocity; too high or too low. Clean the barrel to a gleaming shine, apply case lube to a lead bullet, and tap it thru the bore. If rifleing is very shallow >> need a larger diameter bullet, deep rifleing >> soft bullets or too much powder. End result: another reason to buy more reloading and shooting accessories .

A bullet stiking a target sideways has awesome knock down power, depending where the impact strikes the target.

One day of exceptional performace with cast lead bullets, I never touched the 8" diameter bullseye on the 24" square paper target. I did hit the 3/4" pvc pipe frame of the target holder on both sides and the top. Amazing accuracy with shattering knock down power.

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S&WHF 366

Pipe, Hacksaw, Tailgate. Rinse and repeat.


FF - Ratchet that load down to 4.0 and see if it settles in.

So I have very similar behavior when using undersized bullets (I reload 45acp bullets for 455 webley and see keyholes every time just about). However, I doubt that the barrel diameters differ from spec all that much to cause the weird behavior, but it's still worth a check.

Keyholes are likely the result of poor stabilization as said already, but I think a factor here could be the twist rate of the two barrels. If the two barrels have different twist rates (the XDm is 1 in 16 and the 9c is 1 in ~18.75 if I remember correctly) it is possible for proper performance in one gun but not the other. Velocity is also a factor here, so a given velocity at a given twist rate may work, but a different velocity may not. If you have chrono data, use a miller twist rule calculator and check the gyroscopic stability factor, IIRC it should be around 1.5 to 2, values much much higher can also be detrimental via overstabilization.

I 2nd this. Your load sounds a bit hot for a lead projectile.

What are you sizing your projectiles to? Projectile sizing matching bore diameter also needs to be checked.

I had some problem in 9mm bullets tumbling when using a lee tuble lube mold. I think the thin driving bands on the bullet did not stabe
lise the bullet. I sent the mold back and got another with wider bands and problem was solved.

If the bore was too big, there would have been leading. If the bullets were skipping over the lands there would have been leading.

The rate of twist is my first guess too.

Was he sure they were tumbling? If they were hitting sideways it would have made a hole that looked like the bullets profile. And, to make it easier for me to find it, where did you get your load data?

In my experience tumbling has always been one of two things. Either the bore was too big for the bullet or the load was too hot. Backing down the load is the easiest to check but I suspect that in this case it is the bore diameter as the loads shot well in one gun and not the other.

The nice thing about cast bullets is that it is real easy to get them sized to fit your gun.

The load data given is withing Hodgdons data for that bullet. The XDm has "match" barrel and as mentioned probably a different twist.

What brand bullet was it? Perhaps try another brand. I shoot MBC lead bullets from my XDm and have no issues.

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Still Running Against the Wind

The bullets were from MasterCast, out of Pennsylvania. They never gave me any problems with the S&W 9-C (when it was mine), or my Browning Hi-Power. My son, the new owner of the 9-C, confirmed the 9-C shot fine. I can only conclude that the one in three guns that had problems (XD-m) was in some way different. I did help him to clean his gun afterwards, by the way, and there was no noticeable leading.

I don't think its a bullet problem. It almost has to be a gun problem, don't you think? He and his guns are now back home in Kentucky, so I've lost the change to mike his barrel.

He put up fresh cardboard, not paper, to prove to me that he was having keyhole hits.

I have to say that 2 other 9mm's in two other manufacturer's guns, had no problem with the rounds. Almost has to be something about his Springer.

Anybody else have issues with loose Springfield barrels?

I live about 5 miles from Mastercast and I've been using their bullets for years. When I first began loading his 9mm bullets, they were "keyholing" for me too. I messed around with powder, powder weight, COL, and even tried the same ammo in different guns. As it turns out, I had the crimp too tight. As soon as I backed off the crimp a little bit, they flew straight and normal. FWIW, I use a Lee factory crimp die in the 4th position on my turret. I raise the cartridge into the die and turn the knob until it touches, then I turn it just another 1/2 turn. This de-bells the case mouth and applies a slight taper crimp. Make sure your crimp doesn't make the case "dig" into the bullet.

Bullets tumble because they are not being stabilized with proper spin out of the barrel. This could be too much velocity for the bullet or too small a diameter that allows the skipping through the rifling and not being imparted enough spin or it could be too low a velocity to have the bullet turning fast enough to stabilize it.

Since your load is at max for that type of bullet I'd suggest you drop your load between 3.5 to 4.0gr and see if it doesn't stabilize.

Leading and bore size would be the 2 places I would look first. 9mm is actually .355 dia, but I seem to recall that S&W uses .357 for their barrels. SA may use .355 and the bullets are stripping/leading the XD bore.

In rifles it usually is wrong bullets for the rifling or twist. You can look at factory specs on both your handguns to see if they are the same.

In handguns I like the suggestions above, drive a soft lead slug thru the well lubed bore. If it appears to be engaging the rifling and full bore it may be driven too fast or the wrong weight. For lead plinkers one might look at a 90-100 grain round nose bullet.

I first became aware of tumbling with an old German MK V Weatherby in 257. 117 gr round nose bullets were OK, 120 Spitzers did not stabilize and key holed. Later MK V's had the right twist....... The gun, whatever it was, that I traded it for made me feel better.......

Well, as mentioned, my son and my (former) M&P 9-C are back in KY. No more troubleshooting when the only gun that had an issue (his Springfield XD-m) is also in KY.

I was expecting to put away the 9mm dies until next year, but now he's asked me to load up a bunch of 147gr for him. The things we do to keep the kids visiting...

Anyway, thanks to all for the thoughtful responses. By the way, I expect to be putting about 2800 Mastercast 9mm, 125gr, conical nose up on the 'for sale' forum in the next few days. Keep your eyes peeled for a deal (or PM me).

All the above notes on loads and bullets bear truth and should be looked into. One interesting item I have not seen mentioned is shooting technique.

My dad was an Army pistol shooter/instructor for nearly 30 years. I distinctly remember hearing stories of keyholing at matches to the dismay of many shooters . The keyholes seemed to be more common with the .38 loads but there were some occassional KH's with the .45 (using handloads) as well.

One of the shooters was able to keyhole at will and keyhole left or right with heel pressure on the grip as the shot was fired . He was able to demonstrate this on both autos and revolvers.

I would suggest adding shooter technique to the list of rule-outs in solving this mystery since a new gun is involved which could affect shooting technique.

The only thing you can do with these bullets is drop the load. Next time order .357" for him.

Before you load any for him, ask him to strip the gun, lube the bbl with light machine oil and push a South Bend egg sinker that just fits into the bbl down it with a brass rod. Then have him send the slug to you. Measure the slug with a good micrometer and see what the problem is. I have my doubts if it is solely rate of twist but loading cast in a 9 or a 40 is similar to loading cast in a rifle. You need to be able to verify fit, function and lube.

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Front sight and squeeze