Reliably Feeding the 452423 - A Science Project

[Bigslug]

EDIT ON 9/30/2014. I'm continuing the my big meplat efforts with a different bullet design. Continue reading this thread, as it's a good primer for what comes next, but the saga continues HERE: http://castboolits.gunloads.com/showthread.php?255216-Feeding-Big-Meplats-in-1911-s-Continued-The-LBT-LFN&p=2951425#post2951425

It's a case of fatal attraction I suppose; somebody with an addiction for 1911's gets into casting, then learns that none other than Elmer Keith designed a massive-meplat bullet for his favorite handgun. It's a given - molds WILL be bought!

I acquired a round lube-groove Lyman about a year ago and experienced a little bit of hitchy but reliable feeding with my first attempt, then got distracted by other stuff. More recently, after reading of other folk's trials with this design, I got to thinking:

Elmer designed this bullet WAY before there were hollowpoint-friendly feed ramps and magazines with feed lips timed for any slug under the sun. He would have been working with GI-standard hardball ramp and GI standard tapering feed lips. Surely, this can not be that hard. Time to shoot a bunch of bullets through a bunch of different guns with a bunch of different magazines and see what happens.

My first batch cast with range scrap dropped heavy, so I poured a couple hundred out of straight Lyman #2 (243 grains), sized them to .452" with Ben's Red and left them in the hands of my dad (The Retired One) who had time to load them atop 5.3 grains of Unique. I gave him an approximate COAL spec of 1.13-1.15. He arrived at 1.18" for reasons I've not discussed with him yet, but they fit the mags, so away I went.

Magazines used were:

Mec Gar 7 rounder (holds the rounds higher than any others in my collection)
Wilson Combat 8 rounder (second highest holding of the rounds)
Older Springfield Armory with a baseplate marked "SA NM" with wadcutter feed lips
Metalform rounder with WC feed lips.
Baseplate marked "Colt 45 Auto"with longer WC-type feed lips.
A newer Springfield 7 rounder.
An old GI tapered lip hardball model.
Para Ordnance P13 - obviously only used in the Para Ordnance P13.

Guns and results:

Circa 2006 Springfield MC Operator running an 18.5# recoil spring but otherwise stock in all the areas that matter here.
Ran 100% on everything but the long WC-lipped "Colt 45 Auto" magazine, which gave 1 failure to feed that could well have been me pushing upward slightly on the slide stop.

While I failed to do this for all mags across all the tests, I chambered, then manually ejected the first round on a few magazines. It is notable that the one fed from the Mec Gar had the least damaged nose of all I checked.

1944-production GI Colt 1911A1. This one has literally been through the wars, but has all its original parts, down to the correct magazine. Oddly, it ran perfectly on the original magazine, the Mec Gar, and the new Springfield mag, but choked on everything else that was designed for wadcutters. Again, the Mec Gar munched the nose least.

Series 80 Gold Cup. The frame was made in the mid-'80's, but the entire gun was factory-rebuilt last spring and is all new parts save the frame, grip safety and mainspring housing. It's got the new-style barrel and feed ramp. It ran 100% on all the mags.

Circa 1995 Para Ordnance P13. Ran flawlessly although it tended to bounce brass off my forehead. The integral feed ramp on this gun seems to get along well with this bullet, and munches the nose very little.

So what this bullet seems to like is a mag that holds the nose of the bullet as high as possible, or the controlled-feed action of tapered GI feed lips.

I am not done with this madness by a long site. Seating depth is the other variable I need to play around with. NOE and Mihec are currently running group buys (yes Virginia, I am waiting on both) which will up my production on both solid (NOE) and HP (Mihec) versions. Hopefully this serves as a helpful P.S.A. and feedback thread for those tinkering with the design. I haven't really wrung it out with this intent yet, but it seems to be a really accurate little bugger. . .

[ddixie884]

Great test and post, THANX for your effort. Your dad too......

[MT Gianni]

IIRC, ELmer designed it for the 45 Auto Rim. I shoot it in a Blackhawk for a fun thumper. I never tried playing with it enough to ensure it fed in the Kimber. Right now it is loaded heavy for the Ruger but your posts are a great read.

[Bigslug]

The thing that I can't decide whether I'm baffled on or not is that the GI hardball gun ran so well with this bullet using the stock GI hardball magazine. Yes, I kind of expected it to, being what was available back in the day the 452423 was developed, but that the gun WILL run on that and NOT on wadcutter mags perplexes me somewhat.

Now that Checkmate is manufacturing brand new mags with the GI lip profile, I think I need to revisit that concept for the .45ACP in general. Most of the modern factory HP's, as well as my Accurate 45-230F, decently approximate the profile of hardball, and I really like the fact that it basically guides the rounds in almost a Mauser 98 fashion. As with so much in the firearms world, we seem to be re-learning the fact that John Moses didn't miss much.

For the Elmer bullet, I plan to look around for mags with the highest possible positioning of the top round. I have a vague memory of Nighthawk running an ad a few years back that listed this as a selling point, but can't recall for sure if it was them or someone else. If anyone can confirm that, I'd be grateful.

[harley45]

I to am addicted to this Boolit, I have a feeling at the right velocity it could be the perfect Hog slug in 45 acp

[StrawHat]

Looking forward to more information.

[kbstenberg]

I am just starting to load for a New To Me Springfield XD 4" bbl. So this bullet "should feed properly" for me. I know no guarantee.
Is it just coincidence that NOE has a GB 6 posts before this post for this bullet

[Bigslug]

I am just starting to load for a New To Me Springfield XD 4" bbl. So this bullet "should feed properly" for me. I know no guarantee.

Based on my currently limited run, I tend to think the more modern guns with the feed ramps integral to the barrel will be fine with this bullet. Bullet ogive was factored into the original 1911 design, which was here a looooooong time before the Speer Flying Ashtray. Most of the recent guns were blueprinted out with those wide-mouth truncated cones in mind - the ramps start well below the nose of the slug. The more recent (last 15-20 years) hollowpoints and many RNFP molds tend to approximate the shape of hardball - albeit with the nose chopped off. The 452423 fits into this category - it has some curve to it, but those nose is chopped REALLY far back.


Is it just coincidence that NOE has a GB 6 posts before this post for this bullet

What? Me stir the pot? Neeeever![smilie=1:

[Ron in PA]

That bullet works 100% in my Colt 1991 ACP

[johniv]

I load this boolit with 6.0 gr of unique but seat to 1.200 col . Cronos at 860 fps from a 5" bbl. One pre series 70 feeds a little rough ,but feeds .The bbl in a series 70 feeds smoothly and reliably.
FWIW
John

[35remington]

The slug was in fact designed for the Auto Rim revolver. Keith said as much.

The Gi tapered lip magazines due to their taper hold the rounds highest of all just before release.....higher than any of the other magazines used. This gives a flatter approach to the chamber and the gun feeds as JMB intended it. What I would have expected is a need to quicken the release timing given your short OAL compared to what the gun normally prefers, but then I have GI magazines that will feed short nose SWC's.

Most other than intended magazines don't live up to the seller's hype.

[35remington]

Describe the nature of the jam with the war Colt using the WC mags.

This will give you the "why" in why they don't work.

[Bigslug]

What we've got is a bullet plowing headlong into the bottom of the feed ramp and stopping.

I figure the parallel feed lips aren't allowing any kind of "nosing up".

There's also the "hybrid" approach to feed lips - the tapered "V" at the rear flaring out to a WC release step at the front. That might be the necessary thang.

[35remington]

Parallel feed lips do allow more nose diving into a feed ramp that is not as deep as later 1911s......because the intended magazines didn't necessitate deeper feed ramps when the gun was built back in the day. This nose diving is a consequence of parallel feed lips holding the rear of the round at the same elevation as the round moves forward. Shorter overall length also causes a later and lower feed ramp strike than a longer overall length, and by extension increases the tendency toward a steeper climb to the chamber even if it gets past the feed ramp. This also makes the rim approach the extractor at a steeper angle and makes it less likely that the round will get under the extractor in the first place.

Pay attention to kachunky feeding is the lesson. It means the gun is on the verge of jamming even if it is feeding.

What is a wonder is that it is not more widely known that parallel McCormick type feed lips decrease 1911 reliability. The 1911 has been tuned over the years to work in spite of the magazines most commonly sold with it. Another irony.

The other factor is that the straight feed lips allow less pivoting of the round near the rim as it goes forward. The taper is more forgiving of variations in feed ramp angle as well has having a more desirable, higher frame ramp strike.

If any jamming due to a low frame ramp strike is occurring it is most likely on the first rounds out of the magazine, as the rounds strike low and then progressively higher as the magazine empties. This is a consequence of the gap between the feeding round and the ones below it, and this gap is most pronounced and allows the most nose diving when the magazine is completely full.

The hybrids have a slightly earlier release point that the Checkmate GI's, and may have a significantly earlier release point that older GI magazines that occasionally release quite late for some of the shorter rounds. It's the release timing that makes the magazines more or less suitable for a given bullet, not the abrupt flare, as the round can release abruptly or gradually without loss of control. The main point in reliability is that the rim is closer to the extractor upon release and the cartridge approaches the chamber at a flatter angle, and the tapered lips of hybrid or GI persuasion provide it.

[Outpost75]

This bullet from Accurate has as large a meplat as #452423 and feeds flawlessly in M1911s.

102126

[Bigslug]

. . .What is a wonder is that it is not more widely known that parallel McCormick type feed lips decrease 1911 reliability. The 1911 has been tuned over the years to work in spite of the magazines most commonly sold with it. . .

. . .The main point in reliability is that the rim is closer to the extractor upon release and the cartridge approaches the chamber at a flatter angle, and the tapered lips of hybrid or GI persuasion provide it.

I've often thought that we should change the First Commandment to "Thou Shalt Not Unduly **** With John Browning's Blueprints". What with the proliferation of rounded profile hollowpoints these days, I think I'm headed towards GI lips for most general purposes anyway.

Next payday is likely to bring an order of two each Checkmate GI and Hybrid feed lip mags for the next round of 452423 crash-testing, which will include Commander and Officer category guns. If anybody is running this slug in Sigs, Rugers, CZ's, or any other non-1911 auto, your data would be most welcome.

[35remington]

I've often thought that we should change the First Commandment to "Thou Shalt Not Unduly **** With John Browning's Blueprints".

AMEN!

Be sure to get the extra power springs for about 2.25 extra per mag when ordering from Checkmate. Not listed in the catalog but they will know what it is when you order them. Cheaper than getting them later, and should be SOP for these 7 shot magazines anyway as they are Wolff equivalent if not actually Wolffs.

Outpost 75's recommendation is excellent in terms of a good bullet, and the wadcutting shoulder is absent so it does not have to cause a possible collision with the narrow hardball throat (really the barrel ramp/clearance) in the older '44 Colt. The slightly rounded ogive is more pronounced than on Keith's bullet and lacks the square meplat edge to hang up on the chamber roof. A rounded ogive, curved meplat edge flatpoint bullet like this is just plain more compatible with a 1911 yet should still be effective in terms of impact.

The wadcutting shoulder is not necessarily a problem in a throated gun, but the shoulder is more pronounced on this Keith than some/most SWC designs normally used in a 1911.

[Bigslug]

I've actually got a happily-feeding .30" meplat mold in the form of my Accurate Molds 45-230F. It's certainly a more reasonably approach to the problem that still has a lot of "ouch" potential. This whole experiment with the Keith bullet could be termed the pursuit of an unhealthy obsession, but it's turning into a good education.

Interesting you should bring up the wadcutter shoulder. In my conversations with Accurate that lead to the purchase of my 45-230F, Tom stated that one of the reasons he put a WC step on it was to give clearance for the internal portions of the slide stop. I wasn't really thinking of this as a potential hang-up location, so I've mainly been looking at the nose of manually extracted rounds.

On the topic of impacting the roof of the chamber, I'm going to have to give that a closer look as well. Appearances seem to indicate only the one hit from the feed ramp - that being greater with some mags than others.

Good intel on the beefier Checkmate mag springs. Since I don't run softball anything, my 5" guns typically get 18.5# recoil springs. A little more steam in the mag to match this would not be amiss.

[Treetop]

Bigslug, thanks for sharing your information re: the 1911 and the Lyman 452423 boolit. I was shooting some of my Mihec clone 454423s through my Rossi lever gun the other day (experimenting with Alliant STEEL in .45 Colt) and even at 50 yards, with my ear muffs on, I could still hear a resounding "slap" as the boolit struck the cardboard target backing.

On the way home from the range I began wondering about how effective that boolit would be, as a self defense/carry gun round. This is still a work in progress for me, and it's slow going because the loads from the .45 Auto Rim load tables will likly produce too much pressure in a 452423 loaded short enough to function reliably in the 1911. My 5" will reliably chamber dummy rounds seated to 1.190" OAL.

I plan on loading some this week with a "sub" starting load of Alliant Blue Dot and work up carefully from there, looking for flawless functioning and a speed of 825-850 fps. if possible.

Edit: I just checked my Lyman 3rd edition and their data was obtained using boolits seated to an OAL of 1.200", so only .010" longer than my dummy rounds. They list a starting load of 6.5 gr. of BD for 654 fps and a max of 8.5 gr. for 855 fps at 13,300 C.U.P. I wonder what that is in PSI? Tt.

[Bigslug]

Treetop (or anyone else with an older Lyman manual), what are the powders and ranges listed for this slug? I'm in the territory of educated guesses when it comes to starting loads.

As to seeing how fast it can be pushed for defensive purposes. . .I'm not really sure that's necessary. I duplicated the 200 grain .38 Webley load with the Lyman 358430 in .357 brass and got 18"+ penetration in FBI gelatin at a starting load that only clocked 561fps. The only reason I can think of to try bolting warp engines to this thing is to get a better trajectory for hunting. Otherwise, no reason to beat the guns up.

Reliability, of course is the greater concern. I think my next round of tests will include something along these lines:

Insert full magazine into a pistol that already has a round in the chamber, fire the chambered round, the extract the first round off the top of the magazine from the chamber, extract and inspect bullet nose for damage. Fire off the rest of the magazine except for the last round - extract and inspect as before. The winning magazine design - probably - will be that which gives the least munching of the noses on both.

[Silver Eagle]

Slightly off topic. Regarding magazine feed ramps, can someone post pics or links to the differences.
I have changed to shooting cast (Magna H&G 68 200 gr. clones) in my Kimber Gold Match. I would like to be able to compare my magazines with others. Also would like the info on what to look for in cast friendly magazines.

[Treetop]

Treetop (or anyone else with an older Lyman manual), what are the powders and ranges listed for this slug? I'm in the territory of educated guesses when it comes to starting loads.

As to seeing how fast it can be pushed for defensive purposes. . .I'm not really sure that's necessary. I duplicated the 200 grain .38 Webley load with the Lyman 358430 in .357 brass and got 18"+ penetration in FBI gelatin at a starting load that only clocked 561fps. The only reason I can think of to try bolting warp engines to this thing is to get a better trajectory for hunting. Otherwise, no reason to beat the guns up.

Reliability, of course is the greater concern. I think my next round of tests will include something along these lines:

Insert full magazine into a pistol that already has a round in the chamber, fire the chambered round, the extract the first round off the top of the magazine from the chamber, extract and inspect bullet nose for damage. Fire off the rest of the magazine except for the last round - extract and inspect as before. The winning magazine design - probably - will be that which gives the least munching of the noses on both.

Bigslug, the following information is from the Lyman Cast Bullet manual, third edition, page 283. Bullet # 452423, OAL=1.200". Bullets cast from Lyman #2 alloy.

700X 3.7 gr.-620 fps, 4.5 gr.-755 fps

PB 3.9 gr.-535 fps, 4.8 gr.-890 fps

SR7625 4.1 gr.-505 fps, 4.9 gr-655 fps

Bullseye 3.0 gr.-500 fps, 4.5 gr.-720 fps

Red Dot 3.5 gr-590 fps, 4.3 gr.-715 fps

Green Dot 4.0 gr.-605 fps, 4.8 gr.-715 fps

Unique 4.8 gr.-585 fps, 6.0 gr.-750 fps

Blue Dot 6.5 gr.-654 fps, 8.5 gr.-855 fps

HS-7 8.0 gr.-757 fps, 9.3 gr.-864 fps

They also list charges for two obsolete powders (W/W 630 and Alcan AL-8). Let me know if you are interested in these particular powders and I will list them also. Tt.

[Bigslug]

Bigslug, the following information is from the Lyman Cast Bullet manual, third edition, page 283. Bullet # 452423, OAL=1.200". Bullets cast from Lyman #2 alloy.

Ferris Bueller, you're my heeero!:happy dance:

Edit to add - do they have any comments regarding the slug's use in the ACP?

[Bigslug]

UPDATE: My Checkmate magazines arrived in the mail today - two GI and two hybrid feed lips. Continued and expanded testing soon to follow!

[harley45]

Can't wait glad I'm following this one

[Bigslug]

So what I ended up doing today with the 1944 GI and the Gold Cup:

I loaded one each of the Checkmate hybrid and GI, and a Mec Gar 7 and 8 rounded to capacity, manually chambered the first round, then ejected it. I then loaded three rounds into each of those magazines, fired one round, then ejected the second. Finally, I loaded two rounds, fired the first and manually ejected the final round. I Sharpied each round and then placed the three from each gun/mag combo in their own baggie. Going to do the same thing for the Springfield and a Combat Commander a bit later. I have access to a Springfield Micro as well - - I'll just have to see where this road takes me.

This will let me compare the damage inflicted to the meplat throughout the process feeding the entire stack, all the way from maximum spring tension with a full mag to the slightly different feeding of a round with a follower instead of another round beneath it. Without having fully studied them yet, it's pretty obvious that the first round takes the greatest beating because the extra spring pressure does not allow it to nose up as easily. Some of the rounds from the end of the magazine were almost pristine in comparison.

What's really interesting is that the nose impacts are on the 4:00 and 8:00 positions of the meplat - not at the 6:00 like you might initially think. This is most pronounced on the GI gun, as it seems to have the narrowest frame ramp to negotiate. But the main thing is that it feeds well in a stock military gun without needing "special" mags, and it shoots to the sights out to the 25 yards I had available today.

The data will firm up over the next few days one I have a big enough pool of it to swim in. Stay tuned!

[StrawHat]

...What's really interesting is that the nose impacts are on the 4:00 and 8:00 positions of the meplat - not at the 6:00 like you might initially think...

Are you indexing the rounds as you put them in the magazine?

[Bigslug]

Are you indexing the rounds as you put them in the magazine?

Not so far. It's pretty obvious what's going on - the ramp portion of the frame (at least on the GI gun) is set up to take a smaller meplat than the 452423. Where a more tapered slug might show signs of a single-point strike at 6:00 somewhere along the ogive, the 452423's are getting nicked on the corners of the meplat where they contact the SIDES of the frame ramp. The Para Ordnance (ramp integral to the barrel) did not do this - it had a slight smearing of the corner centered at 6:00.

What they are NOT showing is signs of any significant impact on the top of the chamber from nosing down, so the slug has enough ogive to easily handle that part of the problem. MORE DATA TONIGHT!

[Sgt Petro]

Thanks for all the info, Bigslug.
Looking forward to future data.

[Bigslug]

CONTINUING FROM WHERE I LEFT OFF ON POST #26...

I did the Springfield Operator and an early 70-Series Combat Commander today. Several consistent threads seem to be appearing across all the guns:

1. The first round off the top of a full magazine gets the most nose damage. This has to be due to the fact that as the nose hits the ramp ad starts angling upwards, the tail of the round cannot drop appreciably because the magazine spring is bottomed out. Consequently, the path of least resistance is for the 4:00 and 8:00 corners of the meplat get slightly smooshed.

2. The next-to-last round usually has significantly less damage to the corners of the meplats.

3. The final round coming off the follower is least damaged of all - a fair number of them passing for never having been loaded.

My biggest sample piles are from the Checkmate GI and Hybrid, as well as a Mec Gar 7-rounder. If I had to declare a winning magazine based on least amount of nose damage, it is very close between the two Checkmates - the tapered GI lips maaaaaybe having a slight edge.

I want to do some more tinkering with what appears to be a post-war GI contract mag. Baseplate is marked "19200-ASSY5508694 MFR3075" that has very short, parallel wadcutter-style lips. I only collected rounds from the Commander with this one, but the slugs look very good.

BUT HERE'S THE MAIN THING I'M LEARNING: It is not difficult at all to get this bullet to function extremely well in a 1911. I was expecting a lot of hitchy-feeding in certain guns and magazine types that would not function. This has not happened. Yes, the GI gun had some issues with a lot of the "wadcutter" style magazines, but aside from that, they spit downrange with boring regularity

[35remington]

The rounds climb the ramp as the magazine empties, with the last round striking very high near the barrel ramp.

No issue magazine in GI persuasion ever had parallel feed lips. Very likely it was modified.

The first round dips lowest on the feed ramp because of the large gap between the feeding round and the one below. This provides the room for the nose of the round to dive deepest before it hits the ramp.

Magazine spring pressure isn't the reason for it. The round simply has more room to nose dive when it's the first one in a full stack.

Compare visually to a magazine with only 3 rounds in it.

[Bigslug]

No issue magazine in GI persuasion ever had parallel feed lips. Very likely it was modified.

No tellin', but it looks for all the world like it was built that way. Lips nicely rolled over, even length, uniformly rounded at the front. Even bluing, with some bronze coloration along the front surface where the tube seam was brazed together and where the base plate was attached. Flat follower with a dimple. If it's a home chop-job, it's a damn good one.


The first round dips lowest on the feed ramp because of the large gap between the feeding round and the one below. This provides the room for the nose of the round to dive deepest before it hits the ramp.

Magazine spring pressure isn't the reason for it. The round simply has more room to nose dive when it's the first one in a full stack.

Compare visually to a magazine with only 3 rounds in it.

Ah so! I think my next task is to borrow the Springfield Micro and track down an Officer's Model to run some of my remaining rounds through them for the purpose of seeing how a 3" gun handles them.

I think I'm mainly dealing with an almost purely academic pursuit at this point - from a functional standpoint, they're feeding, extracting, and ejecting without any grief, and it took no effort to get here. Yes, the noses from rounds at the top of the stack get a little whanged going into the chamber, but accuracy doesn't seem to suffer - at least for the purposes a .45ACP is commonly put to (if you're competing for fortune and glory at Camp Perry, I'm pretty sure you won't be using this wrecking ball)

I DO however, want to tinker with getting the smoothest feed of the top rounds possible, so when I revisit this, the project title will probably change to "CLEANLY feeding the 452423". I will need to study some magazine options to see if there's been some additional rocket science directed at addressing the gap 35remington refers to, but I think the focus is going to get directed towards varying seating depth and seeing how that interacts with the release points of the feed lips on various magazines. All of that is going to have to wait until the group buys for the NOE and MP finish up and I have something bigger than a two-cavity mold. The test rounds to this point were made on a single stage to test the concept. Now that I know I'll be tooling up for usable rounds, the Dillon will enter the arena.

My primary goal was to determine the veracity of reports that the 453423 is a bullet that 1911 shooters would do better to avoid. I hope that I have adequately put that issue to bed. Is there stuff out there that will feed smoother? Sure. Do we need to fear this boolit design from a functional standpoint? No. . .at least not so long as we're behind it.:mrgreen:

When I resume the pour, I will almost certainly do some Colt/Auto Rim/Webley revolver work with it, though I think that there's nothing that really needs to be proven in that area. I may also hit up some friends for the loan of their non-1911 autos to see how it does over feed ramps and magazines more modern and less varied in design. If there's anything else you want to see tested with this slug, lay it out!:drinks:

[35remington]

"The gap" cannot be addressed by switching magazine types. All have it. The way to avoid a low frame ramp strike is to avoid straight lip wadcutter magazines and short OAL ammo. Neither caters to the 1911's preferences in feeding.

[Bigslug]

35remington: Thanks so much for your posts, as they've given me a greater insight with which to ponder the issues involved. I begin to see that what we're dealing with is something akin to what gives an AK-47 magazine its distinctive banana curve; stack enough rounds at a certain angle, and they're going to start laying a certain way. In the case of .45ACP rims in the 1911 mag well, this means an increasing gap between the noses as the height of that stack increases.

What I find fascinating about this is that it means the nose damage I'm seeing on the first round from the magazine is due almost entirely to its nose rotating DOWNWARDS into this gap, rather than as a result of the forward motion of the slide slamming the round FORWARDS into the ramp. In this, I see how loading to maximum workable COAL will help place that downward strike more on the ogive, rather than on the edge of the meplat.

On studying these rounds in one of my GI mags, I'm coming to appreciate that Elmer was a pretty clever guy, and that he HAD to be at least in part thinking 1911's with this bullet (and not just the Auto Rim). When given the first forward nudge from the slide, the .34" meplat of the first slug dips because of "the gap", but not until it has moved forward enough to clear the front/right side of the magazine box.

It looks like the pre-requisites to running the NOE group buy have been met, so hopefully we're only a few weeks out from being able to fine-tune this concept in style! TO BE CONTINUED!

[35remington]

The angle of the magazine and the column length cause the gap, and since all 1911 magazine types have this same angle, the only thing that can increase the top round gap is lengthening the ammo column, which means 8 round and 10 round magazines have more top round gap than seven rounders. 10 rounders have especially low first round frame ramp strikes. Bad idea, all of them.

It also means when all the various types have four rounds in them they have pretty much the same top round gap, which is to say less than when the magazines are holding more ammo.

Our insistence on feeding 1911's with too short ammo and with incorrect magazines has necessitated the deepening of the frame ramp into the magwell so the ramp can "catch" the low frame ramp strike instead of having the round nose into the more vertical magazine well. With ball ammo and tapered lip magazines the need for a deep frame ramp is nil because the nose of the round doesn't strike that low.

The problem is......short ammo and low frame ramp strikes means the round's subsequent climb to the chamber is steeper. The steeper climb means the rim approaches the extractor at a steeper angle and is less likely to get there. If the rim doesn't get under the extractor, the gun jams.

So short ammo and straight feed lips make the 1911 less reliable. So we tried to find a way around that, but the fact remains that short ammo and straight feed lips on magazines are a less reliable way to feed the 1911. If they were not.....JMB would have designed a gun that was shooting shorter ammo and would have designed a magazine with straight feed lips. The fact that he did not should make everyone's light bulb go on, but tragically for most 1911 shooters they don't think about the issue that much.

The sides of the feed ramp are actually shaped to "point" the nose of the bullet at the chamber after it glances off the feed ramp. Another way to get the controlled feed envisioned. A low(er) frame ramp strike enables the bullet to get dinged by the frame ramp sides near the top.

The cocking rail hits the round high on the rim in feeding, and the first round pretty much has to nosedive, and more so than the nosediving of the subsequent rounds. No choice. How far it nosedives depends upon the gap beneath and how soon it hits the frame ramp, but the nosediving takes time and room, and a short OAL round provides the time and room to do so.

The last round out of the magazine of a long length ball cartridge doesn't hit the ramp low at all, but rather quite high. Even the first round out of the magazine when it is fully loaded doesn't hit that low with ball, especially out of a tapered lip magazine.

A short button nose SWC that is the first round out of the fully loaded magazine hits the frame ramp quite low, and possibly lower than the frame ramp is present in an unaltered GI gun that has a shallow frame ramp. A straight lip magazine exacerbates the nosediving because the rear of the round stays low in the magazine as the round goes forward in feeding. A tapered lip magazine allows the rear of the round to rise as it goes forward, making the round approach the chamber at a flatter angle, and making the rim of the cartridge approach at a less divergent angle to the extractor hook.

[Bigslug]

So short ammo and straight feed lips make the 1911 less reliable. So we tried to find a way around that, but the fact remains that short ammo and straight feed lips on magazines are a less reliable way to feed the 1911. If they were not.....JMB would have designed a gun that was shooting shorter ammo and would have designed a magazine with straight feed lips. The fact that he did not should make everyone's light bulb go on, but tragically for most 1911 shooters they don't think about the issue that much.

He sorta had a couple - the 1902-1903 .38 autos used two links that caused the barrel to drop downwards, but parallel to its locked-up location. By all reports, it gave the round a wonderfully straight shot into the chamber. Unfortunately, kinda wimpy from a structural standpoint.

He also had the 1890/1906/62A series .22 pumps that used the straight-line "torpedo loading" premise much like the Pre-1876 Winchester levers. Tricky to adopt to an autoloading pistol, but no pesky ramping issues on those!


A short button nose SWC that is the first round out of the fully loaded magazine hits the frame ramp quite low, and possibly lower than the frame ramp is present in an unaltered GI gun that has a shallow frame ramp. A straight lip magazine exacerbates the nosediving because the rear of the round stays low in the magazine as the round goes forward in feeding. A tapered lip magazine allows the rear of the round to rise as it goes forward, making the round approach the chamber at a flatter angle, and making the rim of the cartridge approach at a less divergent angle to the extractor hook.

Hmmmmm. . .I've only recently started looking at the game of Bullseye pistol, so have never really looked into many of the technical details. I DO know, however, that those guys only have to worry about strings of five rounds at a time. I wonder how much - if any - bearing that had on the designing of the HG68 and other similar players.

[35remington]

A lot of bearing on the designing of the 68, I'm sure. Five rounds at a time means only four in the magazine and one up the spout, as the first one would be hand fed and would not be an issue in timed fire. That probably helped resolve some of the feed issues with the short rounds as well, which are somewhat less "divy" than when the magazine is full.

My intended point was that if straight feed lips were right for the 1911, he would have used them. As you mention, he had used straight feed lips in earlier autoloaders designed by him........and deliberately chose NOT to use them in a 1911. There was obviously a reason why, which was to reduce the angularity of cartridge approach.

[Bigslug]

The game goes on. . .

I received my shiny new 5-cavity 453423 from NOE middle of last week and fired it up for the first time today. A few notable differences with the rounded-groove Lyman 2-banger I've been using:

My new operating procedure for a new mold is to do the first cast out of Lyman #2 - at least if that alloy is even remotely appropriate for the design. As data gets compiled, I have a consistent baseline to go off of for whatever comparison needs to be made.

The new mold drops them within less than a grain of the Lyman - call both of them 243 grains. The NOE mold, however, is dimensionally different in several significant ways:

1. While the overall length of the drive band section appears to be identical on both slugs, the NOE has a longer nose giving it an OAL of .651" vs the Lyman's .643. I LIKE THIS! This will give greater COAL without needing to bring the driving band as far outside the case. The two post-WWII Colts I shot with the Lyman set for 1.18" had very difficult manual extraction of a chambered round due to the front band engraving on the leade. Hopefully less of an issue with this new mold.

2. More W.C. shoulder. Measuring just ahead of the front driving band, the new NOE is .400" vs. .411" for the Lyman. Possibly a little cleaner hole in paper with the new one - implications for feeding with the resulting longer nose to be determined.

3. A LOT MORE LUBE! The groove on the new mold is longer front to back, deeper (.382" diameter inside the groove vs. .390" for the NOE) and isn't losing capacity to rounded corners.

4. More bearing surface. Most notably, the NOE has a beefier .11" rear driving band vs. the Lyman's .087. Front bands are at .092 for both and the middle band is .10 for NOE and .105 (approximate). Best I can tell, it's about .302" total bearing surface for the NOE and .284" for the Lyman.

So, same amount of metal, but probably more effectively shaped for the autoloader project. I should be sending the first ones downrange this Friday, so we'll see if what I've learned on first-round nosedive can be put to good use. The chrono will probably be coming out for some rifle work, so I'll be able to see what difference bearing surface alone makes to speed. Look for the bump on Friday night!

[Bucking the Tiger]

Hello Bigslug, I also purchased a NOE 5 cavity 453423 last week. It, like my other NOE molds, is a beauty.
I am going to use it as a light bullet in the .45 Colt and try it in my Gold Cup. I really appreciate this useful and timely post!

[Bigslug]

Bucking,

My pleasure. I too have Gold Cup issues to resolve. The old GI gun has been my FEEDING test bed, based on the assumption that if this slug will chamber in it, the modern ramps will be no problem, and so far, this has been the case.

The slight nose-battering on the first round off the top of the magazine I should be able to largely resolve by increasing the COAL to as long as will function. Only problem with this - from the Lyman mold, anyway - in the new Colts is their shorter throat making manual extraction difficult when seated this way. I doubt sizing down them down to .451" will rectify this, especially when seated longer than I currently have them, but I plan to do a final pour from the Lyman to test this out - for data collection if nothing else.

As said in my last post, the longer nose of the NOE should help with this - it will be tested at .451" and .452" The good news is that this particular test won't require firing, so less production required.

Another noteworthy item - when cast of #2, the NOE dropped at .455". I definitely will be doing the actual production out of an alloy that's softer and more shrinky.

And whenever the MP Molds group buy finishes up, I'll have THOSE specs to compare. Science marches on. . .

[Bigslug]

More a cautionary tale today than a progress report.

Had a 6:00 case head burst in the Springfield today. No harm done to people or gun, and not 100% sure of the cause, but a slight out-of-battery condition seems a reasonable possibility. OTOH, could have just been a bad piece of brass.

Seated at 1.175 OAL, most of the rounds pass the drop-into-chamber test on this gun just fine - it's the COLTS that have the short throat that you would tend to expect this in, but I shot a couple dozen of this same load through one last week with no issues other than the sticky manual extraction. Trying to post-mortem it this afternoon, it took seating the bullets back to roughly 1.150 to get the case heads dropping flush with the barrel hood of the Colt we had on hand.

But for certain I am done with Lyman #2 for this particular project - the bullets dropped big because of it (.455) and wouldn't size down past .4525 which may be leaving the bands over-wide. I need to get some slugs at a reliable .451 to fully get a handle on the overall-length / reliable chambering / damaged nose puzzle. Will pour some more and report back.

At any rate, please do the drop-in-chamber check on your initial rounds - it's not just for checking taper-crimp anymore!

[35remington]

BigSlug, for reasons that have been gone over many times before, oftentimes here by myself, out of battery firing absolutely, positively cannot happen in a 1911.

I will follow up on that statement if need be. Multiple things prevent it from happening, and it does not rely on the proper functioning of a safety to prevent out of battery firing. You'll need to look for another cause. Brass or load.

Here's a quick lead:

http://www.americanclassic1911forum.com/forumsii/showthread.php?677-FIring-out-of-Battery-The-myth

[Bigslug]

Well yes, I understand angles of hammer impact and all that, but I also try real hard to avoid phrases like "absolutely, positively"... The rounds as they're dimensioned don't seem to have any issue (at least on the ones observed) engraving into the lands and getting to proper headspace on the short-throat Colts (which this ruptured case did not occur in), but I have to acknowledge that they at least have the potential to push the slide into that tiny window of "not forward, but not back enough for the disconnector to depress". On this gun, that window is about a sixteenth of an inch. Allowing the slide to travel forward, there's the main travel where the disconnector is fully depressed and nothing happens when the trigger is pulled, then there's a VERY small window where the slide is not fully forward but the firing pin still gets enough of a hit to kick a rubber-erasered pencil out the barrel. Sure, the locking lugs are still engaged, but the gun is closer to linking down than it would otherwise be.

I'm not the sort to ego-trip and say that a double charge wasn't possible, and the primer dimple was flattened back out, but the gun is undamaged. A double charge in this instance would have been 8.8 grains of Titegroup behind a 243 grain slug. Probably in the +P or +P+ range. Likely enough for a brass rupture, but probably not a gun rupture. The brass probably had not more than a couple of firings at hardball spec, but who can tell at this point if it was the one the elephant stepped on and ground against a piece of glass?

The cartridge dimensions as loaded almost all passed the drop test into this Springfield's chamber, but a few of them didn't. None of them passed it in the Colt.

Whatever. That I'm OK and the gun's OK are what matters. The variables abound, it could be more than one of them at play, and there's no way to tell for sure after the fact what the combination was. The moral of the story is, when you walk off the reservation, walk slowly and look twice at the things you THINK you understand.

[Piedmont]

I blew a case head in a 1911 more than twenty years ago. It made me very cautious with the autos. If I want power from a handgun with my handloads I grab a strong revolver and proceed. There is no weak point at 6:00 in a revolver chamber.

[35remington]

"Sure, the locking lugs are still engaged, but the gun is closer to linking down than it would otherwise be."

And there's the rub, and why the gun can't go off out of battery. The link does not have the wherewithal to pull the barrel out of battery when the bullet is still in the barrel, as the shear forces holding the lugs in engagement are far larger than a link can tug out of battery, or the forces driving the link can overcome.

The barrel lugs aren't just in sliding contact with the slide's lug recesses while the barrel is pressurized and the bullet is in the barrel.....they're pressing, very, very hard against them.

The only time and place where pressure is high enough for the case to blow with any violence is when the bullet is near the chamber, and quite clearly the gun couldn't link down then even if there was no pressure holding the lugs in engagement. The bullet would be much farther down the barrel or gone before the link started pulling hard due to the great differential between bullet weight and slide/barrel weight.

So there's still time for the bullet to exit before the link starts pulling seriously whenever the lugs are in engagement enough for the gun to fire. Reread Tuner's "and even if" paragraph near the bottom of his post.

And to recap, the shear forces are of such a nature that the link couldn't get it done. The bullet is forcing the barrel forward, and the cartridge is driving the slide rearward with very substantial force. If the lugs are engaged even partially when the gun is fired.....and the 1911's operating tolerances see to it that the lug engagement is sufficiently substantial or the gun won't fire....the lugs stay engaged until the bullet exits. If the barrel can't be out of battery until the bullet is gone, the case can't blow.

Can't happen any other way, no matter what. Ever.

Out of battery firing when the trigger is pulled is an imaginary event in a 1911. Same with Glocks. Better to revisit the bad case theory or variance in charge weight. The nature and shape of the blowout may give a clue.

[35remington]

For the sake of really dispensing with the idea of an out of battery firing with a pull of the trigger blowing the case, let's make a few ridiculous assumptions that invalidate the argument, but in fact further serve to make the point that out of battery blowouts from a pull of the trigger can't occur.

Let's assume the link can pull the barrel out of battery because the lug contact is completely frictionless while the bullet is in the barrel and it is pressurized. Yeah, completely wrong, but bear with me.

I measured some White Box WW ball at between 1.260 and 1.265" OAL......let's call it 1.263" OAL average. A Hornady bullet in my collection of 230 grain FMJ construction is .645" in length. Therefore the base of the bullet is about 0.618" from the end of the chamber when it's fired assuming reasonably flush hood fit with the slide.

The slide moves 1/34th the speed of the bullet because that's the ratio of their masses. Therefore, given the numbers above on the minimum side, the bullet's base is 3.4 plus 0.618 inches down the barrel in the .100" of slide movement mentioned, or 4.018" down a 5 inch barrel. That places it 0.982" from exiting. At this point the lugs have disengaged and the slide is now free to move backward from the barrel in our assumed frictionless lug engagement environment. Let's also forget the barrel has not hit its bed in the frame at this point and is still pivoting and going backward a little itself, which means the breech is not moving away from the barrel as fast as it is in later points of its movement.

How far does the slide move given the bullet must go 0.982"?

0.982"/34 =0.029."

So.....during the time the bullet is in the barrel, and assuming the link even could pull the barrel out of battery, the case is withdrawn 29 thou from the chamber's normal supporting position. This is a bit over two case mouth thicknesses, or, in other words, not much.

What is residual pressure when the bullet is this far down the barrel? We do know it's much lower than the peak pressure given the distance of travel. We also know that at this location of the case wall, 29 thou out, the case wall thickness is still greater than case mouth thickness as it's still the tapered region of the case. Given this lower residual pressure, and given the location the pressure has to work on in the case, the very very worst case scenario might produce a very slight case wall bulge, but it is much more likely that there would be no evidence of it whatsoever.

And all this would be discounting the difficulty of pulling the lugs out of engagement with the link in the first place when the bullet is in the barrel. And also discounting the fact that the barrel is still pivoting downward and back slightly, which would place the actual separation at somewhat less than 0.029."

That should do it for out of battery firing blowing a case. Can't happen.

[35remington]

Monkey with your 1911 and witness the distance the slide can be back and still have the hammer fall with the lugs still in engagement (gap your calipers at 1 1/10 inch and compare, realizing that the .100" assumption was made on a hammer not striking the firing pin due to interference with the firing pin stop at a minimum of 0.110" out, not on actual slide movement to allow hammerfall, which is somewhat less, obviously). On my Colts, it is indeed somewhat less than the one tenth inch mentioned above, which further points out the flaws of the one tenth of the inch assumptions made. This further kills the out of battery blowups with a pull of the trigger idea.

[Treetop]

Thanks for that link and your explanations, 35remington. The more I study the wonderful old 1911 design, the more admiration I have for John M. Browning! Tt.

[35remington]

Most autoloading pistols today are copies of what he did in terms of operation....even Glocks.

[Bigslug]

Time to put the closer on this, methinks, as I think my last question has been answered. I did some manual-feed testing today in an loaned 1945 Ithaca/GI mag combo (unaltered save for an 18.5# spring) with some dummy rounds I made up. These were seated deliberately long to the crimp groove to see if it would improve overall quality of feeding.

I think I have demonstrated adequately that getting this slug to feed reliably is not a serious challenge. Real-world, functional accuracy? Also no problem. Getting all seven rounds to feed pretty with the .34" meplat still unblemished coming out of the barrel is another matter entirely - at least in the more-or-less "standard" 5" 1911, two-piece ramp configuration. The 4:00-8:00 edge of the meplat invariably gets rolled over to varying degrees depending mostly on ramp design, magazine design and location of the round in the stack (1st, 3rd, 7th, etc...). Seating long didn't really seem to change much in that area.

Worthy of note in this test is that I was finally seeing 12:00 strike on the nose where the bullet hit the top of the chamber prior to nosing over. Whether that's due to the longer COAL on these dummys or something peculiar to this Ithaca is hard to tell without testing other guns, but I would bet it's COAL.

So, conclusions by way of bullet points:

*Ramp design matters a little, but not nearly as much as mag design. If you've got an integral ramp gun, nose damage may be less.

*Longer COAL MAY help with reliable feeding (shorter didn't seem to have any real problems), but the WC shoulder of this design MAY stick in a shorter/tighter throat. You are going to have to balance ideal feeding length with a WC shoulder placement that will allow for manual extraction without strain.

*Pay attention to your taper crimp. This slug takes a bit of a beating on its way into the chamber, so take steps to ensure it doesn't get jammed back into the case.

*If you've got an integral ramp gun, nose damage may be less.

*Penetration capabilities are impressive, at least from the relatively unscientific row-of-water-filled-milk-jugs viewpoint.

*The hole it makes in paper is very pretty - munched noses or not.

Many thanks to 35Remington for his input on the intricacies of 1911 feeding dynamics. This would have taken considerably longer otherwise.:drinks:

I think what we have here is an ESSENTIAL mold design to have on hand for moderate .45 Colt loads and the ACP revolvers. It is quite serviceable for .45 ACP automatics, but not, I think, the ultimate slug for the task. I'll still be working on that, but probably not until AFTER deer season. The madness shall continue!

[StrawHat]

Thank you for putting your thoughts and research to writing. I have learned from this thread. I have the GB 452243 and haved used it in the S&W revolvers but now I have a bit better feel for getting it to work in a Series 80 Colt.

[harley45]

This was a good post on one of my favorite boolit designs! I never had any trouble with it feeding and I still learned from this thread!