.40 S&W reloading problem

[oldhenry]

I don't own a .40 S&W, but a close friend & a grandson-in-law has one. They don't reload & don't practice much. Recently I was able to get a classic Lyman AA turret press from a forum member (excellent condition) & thought I'd make it a dedicated .40 S&W press. For dies I chose the Dillon because I use them exclusively with my 2 550s. For an exp. die I'm using a Lyman M die from my .38-40 set & I'm using my Little Dandy (hand held) to do the powder measuring. I settled on 4.7gr. of HP38 & the Lee 401-175 with CCI 500 primers. Luckily I didn't mass produce, but loaded 25 in Winchester cases.

After sizing I gave all cases the "plunk" test in my friend's Tarus 740 "Slim" (they passed) & after loaded "plunked" them again. I then loaded 18 (3 mags. full) of mixed head-stamped cases
that sometimes give me problems loading 9mm: CBC, S&B. That 18 also included PMC, Fiocchi, GECO, Perfecta, HRTRS & WMA. Loaded, they all passed the "plunk".

I intended to shoot the 18 as a test & mass produce if they were OK. The problem surfaced before the shooting could take place: I was unable to load them into the magazine. The 1st. round went in OK, but the 2nd round was very difficult. When I attempted to load the 3rd.round, the 2nd, round would wedge & prevent the loading. Withdrawing the attempted loading of the 3rd. the 2nd. round would not rise up into feed position. I had to bump it several times to dislodge #1&#2 to get them out of the magazine. I tried different head stamp reloads & they all did the same thing.

I then loaded the mag (with some difficulty) with my friend's factory ammo (Fiocchi HP, weight unknown). The design of the magazine is such that the #1 goes in OK & the loading of the #2 is only possible by forcing the forward part of #1 down which cocks-up the rear of #1. Even though the loading was difficult, it was possible with factory ammo.


I did some measuring & the head of his factory loads measure .417-41750. Immediately forward of the extraction groove they measure .420-.42050. The Win. reloads measure .415-41575 at the head & .422-.424 forward of the extraction groove.

OAL of the factory loads is 1.115. OAL of my reloads average 1.118


Federals @ head=.420 & forward of extractor=.425-.42650
PMC=.420 head & .424 forward of extractor
Fiocchi heads=.417 & forward of extractor=.42750
GECO heads=.417 & forward of extractor groove=.426
Perfector= .417 heads & forward of extractor groove=.423
CBC heads =.418 & forward of extractor groove=.425
S&B heads =.421 & forward of extractor groove.42450
HRTRS heads=.42150 & forward ofextractor groove=.423
WMA heads+.417 & forward of ext. groove=.425

The dimensions of the factory ammo & the reloads are slightly larger forward of the extractor groove, but I find it hard to believe that this slight difference makes loading the magazine impossible...……..unless the magazine is on the tight side of the specs. I realize that the Dillon dies are radiused @ the bottom to facilitate use in a progressive press: would a tighter sizing die be the solution?

Has anyone out their experienced anything like this? All opinions are welcome.

Thanks,
Henry

[Petrol & Powder]

I find it hard to believe that a round that will easily chamber (plunk test) wouldn't function in a magazine due to such a small variance in dimensions as the ones you list.

I think you have a magazine problem, maybe even the wrong mag.

[Petrol & Powder]

Check the magazine and make sure it is a 40 S&W mag and not a 9mm mag.

[Walks]

We're did the cases come from ? If they were shot in a factory Glock bbl. Then your loads are suffering from the infamous Glock Smile.

Or else your loads exceed the Overall Cartridge Length that the magazine will accept.
Which is what it really sounds like.

[Mica_Hiebert]

If the brass was shot out of a Glock the base will bulge. They make a push through die I believe called the bulge buster to run .40 brass through. You may also double check the overall length too.

(Didn't see Walks post prety much covered this)

[reddog81]

It's not terribly uncommon for the magazine length to be the determining factor on OAL. Load some rounds with the bullets seated deeper (adjust powder charge if necesarry...) and see if that works. I have rifles and handguns where rounds can pass the plunk test and not fit the magazine. One is a Colt Delta Elite and it has problems with the normal .40/10mm style bullets.

[stubshaft]

Bad magazine or defective follower.

[35remington]

If you do not check OAL you are missing a vital step.

[onelight]

Is the magazine you are loading a single stack? Are you loading FP bullets?

[oldhenry]

In the order of responses:
1. Petrol & Powder: Magazine is stamped PT 740 (see image #1)
2. Petrol & Powder: I agree that there is a magazine problem (see image #2 &#6)

3.Walks: I can't vouch for the firearm the brass came from. The Winchesters came from my range which is used by close friends & family. Since I don't own a .40, I can't say. The mixed head stamps are from a SFRB purchased from a forum member & I knew they were range pickups. OAL of my loads are .003 longer than the factory loads that will load into the mag..

4. Mica Hiebert: Thanks for the info on the Bulge Buster. Where can I get one? As it turns out as you keep reading, I think that's 1/2 of the problem.


5.reddog81: The rounds will fit into the mag., but spring pressure is "big time". (see image #3 for OAL vs mag length). When #3 is introduced the rear of the cartridge is pushed down & binds on the rear of the mag.. (see photo #2). I loaded 4 more with an OAL of 1.108 (.007 less than factory & no improvement)

6. Stubshaft: I think you are correct!

7. 35 Remington: See photo #3 (reload) & #5 (factory round). Also in the original post I indicated OAL was .003 longer than factory round.

8. onelight: single stack & as you can see they're TC (flat point).


Photos:

#1. magazine marking
#2. the 2nd. round stuck in mag, after #1 removed
#3. OAL vs magazine length: not the problem
#4. Magazine full of factory rounds
#5. Factory round OAL vs mag length
#6. .002 feeler gauge is tight fit on right side of magazine against reloaded round. L. side has no clearance!!! Also R side has no clearance between mag wall & rear 1/2 of the brass. This one photo tells it all.

A. right side of mag has barely perceptible low spot in center where numbers are stamped.

B. slight increase in brass diameter + "A" prevents loading.


The factory barely squeezed by the low spot. That's my theory anyway. My plan:

1. try to contact my grandson-in-law (he travels) & see if my reloads will fit into his S&W Shield magazine.
2. Try to remove floor plate on the Taurus & attempt to get more side clearance.

Thanks for everyone's help.
Henry

…………………………………………………………………………………………………………………………………… ……………………….
A real sport involves either gasoline or gun powder...…………...all others are just games

[onelight]

The pics help.
If I was to guess , I would say for that mag. You need a shorter OAL or a round nose or smaller meplat . Some one else may have a better idea. But I think it is the front of the cartridge in that mag causing the problem.

[35remington]

Take the spring and follower out and see if the loaded ammo stacks in the mag with adequate clearance and no binding. If it does or does not you know what to try next.

[onelight]

If the mag works with factory loads then it would be hard to say the mag is defective.
It would seem that adjusting the OAL and powder charge would be the simple test or a different bullet shape , If that does not work then decide if you should modify the mag. This is assuming the mag works with factory loads.

[country gent]

Looks like the small length of full dia bullet is hitting on the radius's to the narrower end on the mag. Make a few dummies .010 shorter and try. Maybe seat to where the mouth and front band line up even. I have had mags vary in what they would accept some over the years. THe plunk test is good but the mag is the first and real point the rounds have to work

[onelight]

Looks like the small length of full dia bullet is hitting on the radius's to the narrower end on the mag. Make a few dummies .010 shorter and try. Maybe seat to where the mouth and front band line up even. I have had mags vary in what they would accept some over the years. THe plunk test is good but the mag is the first and real point the rounds have to work

Yup , my sig p220 mags require a shorter OAL than some of my other guns

[JonB_in_Glencoe]

I agree with those that stated you need a shorter OAL.
I always make some dummy rounds when I'm loading ammo for a new gun. I will cycle the dummy rounds many times.

[Petrol & Powder]

A few points:
The mag seems to have issues with both reloads and factory loaded ammo.
The profile of the bullet used in the reloads may be slightly contributing to the issue but I don't think that is the crux of the issue.
The reloads "plunk test" and appear to be normal in terms of exterior dimensions (no bulges, OAL within limits, good bullet shape - in other words, they should fit & function just fine)


This situation is yet another example of why I refuse to play in the Taurus sandbox. Sometimes you get a good Taurus and sometimes you don't.

That magazine seems to balk even with factory loaded FMJ rounds.

I'd be willing to bet those reloads would fit & function in a number of magazines for other pistols.

My first suggestion would be to obtain a replacement magazine from Taurus. My second suggestion would be to obtain a replacement gun from another manufacturer.

[oldhenry]

Take the spring and follower out and see if the loaded ammo stacks in the mag with adequate clearance and no binding. If it does or does not you know what to try next.

Good suggestion.

Thanks

[oldhenry]

If the mag works with factory loads then it would be hard to say the mag is defective.
It would seem that adjusting the OAL and powder charge would be the simple test or a different bullet shape , If that does not work then decide if you should modify the mag. This is assuming the mag works with factory loads.

onelight,
Although factory loads will load, the loading of them is difficult...…..even the first 1 or 2. I reduced OAL to 1.108 with no success. I'll try shorter.

[oldhenry]

Looks like the small length of full dia bullet is hitting on the radius's to the narrower end on the mag. Make a few dummies .010 shorter and try. Maybe seat to where the mouth and front band line up even. I have had mags vary in what they would accept some over the years. THe plunk test is good but the mag is the first and real point the rounds have to work

The .002 feeler gauge will barely side between the R side of the mag. & the front 1/2 of the cartridge (including the area containing the boolit). The gauge will not go between the rear 1/2 on this same side. The gauge will not go anywhere on the left side. Also please keep in mind that to load this particular designed magazine extreme pressure is required on the front of the cartridge (near junction of boolit & case mouth) so it would seem logical that any loading problem would be for the front of the cartridge to want to dip down on the front...……..this is not the case. After #2 is loaded the binding takes place @ the rear of #2 when #3 is attempting to enter the magazine. Considering that factory ammo or the entire mag is difficult to load + the above leads me to the conclusion that one side of the mag. (probably the L.) is too tight or the entire mag. is too tight.

Holding the flats of the mag up to different angles to a light reveals nothing real obvious, but there's a subtle hints that the area where the numbers are stamped & holes cut could be slightly lower.