1911 trouble feeding

[BC17A]

Which powder coat powder did you use for that?

Powder by the pound, black cherry.

[guy_with_boolits]

I also am a new reloader, loading for a 45 ACP 1911. Heres what you need to do to be able to analyze and solve chambering issues when reloading:

-use the barrel as a measuring device..it must be PERFECTLY CLEAN in the chamber or it will give false results..that means no powder flakes or lead in the chamber

-take the barrel out of the gun of course

-mark your loads and insert them into the barrel, yielding a witness mark that tells you what is hitting

-your cast boolits need to be sized after powder coating. I bought a lee sizer bushing and then had to sandpaper it out a few thousandths to size things to .4535 in order to get better accuracy and no leading

-the powder through expanding die flares the case. you MUST deflare the case or it wont chamber

-the LEE bullet seating die also does a taper crimp, which can deflare the case. However, I found that its basically impossible to get the taper crimp and the seating to occur in the same step accurately on mixed range brass on a progressive load master. I would recommend doing seating and taper crimp/deflaring in two separate steps. If you buy a separate taper crimp die, make sure it tapers just the case mouth and doesnt size the entire cartridge.

-you really should try and figure out what your barrel groove diameter is, so you can know what size your boolits need to be. YES IT DOES MAKE A HUGE DIFFERENCE. You can either measure it directly if you have the right tools (not calipers..need tenths ID measurement tools), or you can slug the barrel and measure the slug with a mic.

-If your rounds are getting stuck in the chamber, but ARE IN THE CHAMBER and are axially in line with the barrel, it has NOTHING to do with the slide release, loading from a mag, etc.... it means your rounds are too big somewhere (probably case mouth not being deflared right).

-I ended up buying a NOE expander die that would expand the case so that case boolits would not get their diameter crushed. This is not a problem with jacketed. (The LEE powder through expanding die only expands the top of the case). This has helped the boolit diameters be crushed less (as evidenced by pulling them and measuring their diameter). I highly recommend.

-You should drill out an empty case through the primer pocket, so you can use it as a test case that allows you to install a boolit, then push it out and measure its diameter, to confirm its not being crushed too much after seating.

[Cosmic_Charlie]

Oddly enough, this thread makes me want another 1911.

[fastdadio]

Oddly enough, this thread makes me want another 1911.

Oddly enuff, I find it odd that you had a 1911, and let it get away.....

[BD]

I make no claims of being an expert in this area, and while I own a few 1911's, (including one that has been in my family for more than 100 years now), my total experience with them is really limited to a little less than 100 examples. But not being shy I'm going to throw my two cents into this discussion.
When JMB designed the 1911, he designed the barrel with a very short "throat". The beginnings of the lands were tapered to facilitate bullet feeding and accommodate slight variations in ammunition and some powder residue and copper fouling build up. I believe that what he had in mind was reliability. 1911s were all hand fit in those days and this was just one step in the process. I believe the issue we we're talking about here came about with the mass produced guns that became very common in the 1980's and '90s. At least that's when I first became aware of it. I believe the factories simply started skipping the step of throating the barrel as it was part of the "hand fitting" that the manufacturers were trying to get away from. In the '90's, when the majority of competition handgun shooters still used 1911s, this step was part of the usual "fluff and buff" that many factory guns received before being put to serious use. Since then, not so much. 1911's are more rare on the line these days and often at an action pistol match it will only be myself and one or two other old farts in the single stack division. So it's been a couple of years since anyone asked me to "fluff and Buff" a new 1911. And nearly as long since anyone from these forums has asked to borrow a reamer.
I wrote a sticky on this subject six or seven years ago which can still be found on the handguns forum on this site. If you are interested in this it's probably still worth the read. In the years since I wrote that DougGuy has made it his business, (literally), to become an expert at this and he really does a great job. At this point he's probably throated more 1911 barrels than I've ever seen, and from what I've seen of his work he's better at it than I ever was.
The bottom line is that if you look closely into the barrel of your new 1911 and the lands are square on the end at the chamber, I think you are crazy not to get it throated as JMB intended it to be. A simple test is to thoroughly clean your barrel and then fire one shot only using your cast boolit load. Then carefully unload and clear the weapon while holding it level and have a look in the barrel. If the ends of the lands are square you will very likely see the little strands of lead they shaved off as the boolit engraved.

[too many things]

i would say all things are covered .

one post was dead on
the manufactures dont want you to reload .
Glock is very good gun for reliable. buddy wanted some cast. the gun jambe twice , he sent it in. they sent it back the next week.
with a very large RED printed note
DO NOT USE RELOADS YOUR WARRANTY IS NO GOOD NOW

[Cosmic_Charlie]

Oddly enuff, I find it odd that you had a 1911, and let it get away.....

Back in 2013 I sold it to my eldest son. I was having some serious motor neuropathy issues and I could not use a firearm or tie a fishing knot. Regular infusions of immune globulin got my function back surprising me and my neurologist. When ammo became plentiful I started shooting again. Started casting too.

[DougGuy]

I make no claims of being an expert in this area, and while I own a few 1911's, (including one that has been in my family for more than 100 years now), my total experience with them is really limited to a little less than 100 examples. But not being shy I'm going to throw my two cents into this discussion.
When JMB designed the 1911, he designed the barrel with a very short "throat". The beginnings of the lands were tapered to facilitate bullet feeding and accommodate slight variations in ammunition and some powder residue and copper fouling build up. I believe that what he had in mind was reliability. 1911s were all hand fit in those days and this was just one step in the process. I believe the issue we we're talking about here came about with the mass produced guns that became very common in the 1980's and '90s. At least that's when I first became aware of it. I believe the factories simply started skipping the step of throating the barrel as it was part of the "hand fitting" that the manufacturers were trying to get away from. In the '90's, when the majority of competition handgun shooters still used 1911s, this step was part of the usual "fluff and buff" that many factory guns received before being put to serious use. Since then, not so much. 1911's are more rare on the line these days and often at an action pistol match it will only be myself and one or two other old farts in the single stack division. So it's been a couple of years since anyone asked me to "fluff and Buff" a new 1911. And nearly as long since anyone from these forums has asked to borrow a reamer.
I wrote a sticky on this subject six or seven years ago which can still be found on the handguns forum on this site. If you are interested in this it's probably still worth the read. In the years since I wrote that DougGuy has made it his business, (literally), to become an expert at this and he really does a great job. At this point he's probably throated more 1911 barrels than I've ever seen, and from what I've seen of his work he's better at it than I ever was.
The bottom line is that if you look closely into the barrel of your new 1911 and the lands are square on the end at the chamber, I think you are crazy not to get it throated as JMB intended it to be. A simple test is to thoroughly clean your barrel and then fire one shot only using your cast boolit load. Then carefully unload and clear the weapon while holding it level and have a look in the barrel. If the ends of the lands are square you will very likely see the little strands of lead they shaved off as the boolit engraved.

BD thanks for your words of wit and wisdom, and thanks for starting that thread so long ago. I can go back in that thread to where I just started taking this stuff in as a service offered, and then come today where I have pretty much dialed in my "philosophy" of how the throat should be, and what I want it to do when a boolit is fired into the bore.

SAAMI specs call for some taper in the throat, and for the longest time I used to see a little ring of freebore between the chamber mouth and the leade ins to the rifling but as you concurred, manufacturers couldn't be bothered to put enough -or any- freebore in there to enable the use of cast boolits without the need for either a compromise or a workaround. If all anybody ever loaded was .451" for the 1911, we would have never been having this conversation and I wouldn't have had a job.

After working over scads of 45ACP cylinders, they were usually pretty darn accurate, moreso after correcting the throats to .4525" but it dawned on me that there was about an inch of smooth parallel freebore, not unsrpported freejump like in a revolver cylinder shooting 38 special into 357 magnum chambers where the boolit has to travel a good ways with nothing to center it or guide it and then WHAM it hits the chamfer at the beginning of the cylinder throat and it gets aligned to exit the cylinder. I am talking about fully supported freebore, smooth parallel throat, and truth be told when it's sized right, these ACP cylinders are REALLY good shooters. I think it makes a great improvement in aligning and squaring the boolit to the barrel more than say a 45 Colt cylinder would do.

Then there came along a process called Taylor Throating which was adapted from the Weatherby rifle maintenance reaming of the throat, but it was adapted to the cylinder window of a revolver so that revolvers could be relieved of thread choke, improperly cut forcing cones or really rough forcing cones, so here a length of freebore about 1.5 times the caliber diameter is reamed into the barrel encompassing the forcing cone, some parallel supporting freebore, and a real gentle 1 degree leade in to the rifling. This worked really well for problematic revolvers, and it exposed what kind of improvement that freebore could make if it was in the barrel, concentric to the bore, and not just the cylinder. Ross Seyfried wrote extensively about the procedure many years ago.

From that, I have "borrowed" a little influence, and I put enough freebore in the throat of a 1911 barrel that the boolit can exit the case mouth, be fully supported by close tolerance freebore, and most or a great deal of the parallel sides, bearing surfaces if you will, are into the freebore where the boolit is held square, concentric with the bore, and perfectly on centerline when it encounters the leade ins to the rifling. It is actually a tool, a precision alignment sleeve, not just a cut for clearance to allow whatever boolit style or COA the shooter wants to use. It is basically the front half of the Taylor Throat profile, cut into an autopistol barrel without the forcing cone.

The longer freebore has a couple of benefits or drawbacks depending how you look at it, the first being there is less resistance to the boolit entering the bore, because it's freebore and not rifling yet, that pressure will not build as high as the same boolit fired right into an unthroated barrel. This is not a bad thing, but since velocity is dependent on pressure, loads can lose as much as 25-30 fps from the lower pressure. All that is necessary is to bump the powder charge a couple of tenths of a grain, or just live with the very tiny change in velocity.

Overall these barrels shoot lights out. I usually throat and crown them, send them out, and most of the time I never hear anything after that unless the shooter has more barrels they would like done. You know if there was a problem, I'd be the first they would be looking to talk to, so I know by that people are happy with the work and the results. Now I'm letting all my tricks of the trade out of da bag..

[charlie b]

Just to point out something that may not be obvious to some.

Powder coating changes the ogive portion of the bullet just enough to make a different OAL necessary in some cases unless the barrel is throated. Even if you size after PC, the ogive section is still a little thicker. This is not just in some pistols, it occurs in rifles as well. All depends on the dimensions of throat and bullet after PC and sizing.

Since the OP's barrel is being throated that should solve the problem with PC and RN bullets.

But, I never did have good luck with the Lee 1R mold. Can't remember much as the last time I used one was back in the 80's Most of the time I shoot either TC or SWC cast bullets in my 1911's.

[Forrest r]

I just find it odd the op couldn't get that lee 1r to function. PC has nothing to do with it. Bought a cheap lee 1r mold for the 45acp's decades ago to keep around for a 230gr bullet. Ran that bullet thru 15/20? different 1911's with no issues. Finely sold that mold off along with a bunch of others, I prefer +/- 200gr bullets in the 1911's.

Been thinning the herd and I'm down to 3 molds for the 45acp's/1911 along with selling off all the 1911's except for 2. Both are box stock springfield armory range officers. They are both setup with burris fastfire III's on them.
[IMG][/IMG]

Was digging around last week and found 3000 wolf lp primers laying around I didn't know I had. I have a bunch 14/15#? of clays doing nothing so I decided to work up some loads looking for blammo ammo/dirt clod killers for range play. I used all 3 cast bullets that I make and used 4.0gr of clays & 4.3gr of clays for test loads. Nothing fancy, sat down at a rolling table/cart @ 50ft with a rest, fired up the reddot and did 5-shot goups/tests with the test loads.
[IMG][/IMG]

The black outer ring is 2", the white inner ring is 1 1/2" & the reddot is a 3moa dot. The h&g and cramer bullets did .7xx" outside to outside and the mihec 200gr hp did 1" outside to outside measurements. Figured I'd try shooting a 5-shot group offhand/1 handed @ 50ft with that mihec 200gr hp/4.3gr of clay just to see what the recovery time would be. Took 25/30 seconds to shoot those 5 shots and managed a 2" outside to outside group. Not the greatest by any means but it told me what I needed to know.
[IMG][/IMG]

Anyone can load/shoot/use the h&g design, the cramer f5 is designed like the lyman 452488 and nose measures .250" long. Both the cramer and the mihec bullets use a short oal of 1.180". The H&G clone uses the standard 1.250" oal.
[IMG][/IMG]

I'm sure doug does good work, myself I just don't see the need to alter the bbl on a springfield ro. Mine is box stock & I haven't had any feeding or jamming issues with it and the 10+ different bullet designs I've ran thru it so far (same bullets pc'd & plain/same oal).

As far as accuracy goes, don't know if there would be much improvement over not having the bbl worked on. I'm the weak link when it comes to the accuracy of these 1911's.

[guy_with_boolits]

The black outer ring is 2", the white inner ring is 1 1/2" & the reddot is a 3moa dot. The h&g and cramer bullets did .7xx" outside to outside and the mihec 200gr hp did 1" outside to outside measurements. Figured I'd try shooting a 5-shot group offhand/1 handed @ 50ft with that mihec 200gr hp/4.3gr of clay just to see what the recovery time would be. Took 25/30 seconds to shoot those 5 shots and managed a 2" outside to outside group. Not the greatest by any means but it told me what I needed to know.
I'm sure doug does good work, myself I just don't see the need to alter the bbl on a springfield ro. Mine is box stock & I haven't had any feeding or jamming issues with it and the 10+ different bullet designs I've ran thru it so far (same bullets pc'd & plain/same oal).

As far as accuracy goes, don't know if there would be much improvement over not having the bbl worked on. I'm the weak link when it comes to the accuracy of these 1911's.

wow so with the MIHEC 200gn hollow point you are getting 1" outer to outer at 50ft (16 yards) so thats more like say 0.6" center to center? So about 3.6 MOA?? Thats impressive.Do you have any other data for that load at various distances? Curious how it maintains at 25yds and 50yds. (Presumably if you dont have a ransom rest or a rest that doesnt move the pistol between shots its going to be tricking maintaining aiming shot to shot)

What alloy are you using? And are you expanding the case? (NOE?)

Ive gotten things to 6.2 MOA at 8 yards with that boolit:

Range pickup jacketed pistol lead with approx 2% tin added.
5.0gn HP-38
Powder coated smokes blue 400F 20mins with water quench after bake
0.456 NOE expander
MP 200gn hollow point mold with round hollow point
Sized to 0.4535"
COAL 1.185"
1911 5" barrel
Mixed range pickup brass
Deflared after seating
Does not seem to be significant/any leading after 100 rounds

Its extremely difficult for me to get good data as distances go up because I'm just using the GI iron sights and I only have a big sandbag as a rest. I cant take myself out of the equation. If I got 4 MOA @ 16 yds I would be doing backflips.

[44MAG#1]

That is very good shooting for sure. Better than most I've seen at the range.
But, the problem in diagnosing shooting ability is difficult at best. If one would look at the group center to center at. 6 inches that would be 3.4377 MOA. If by some stroke of luck that degree of accuracy would continue as the range increases that would equate to a group of 3.599 inches center to center at 100 yards or 1.799 inches at 50 yards. That would be on the verge of a very minute chance one could do that except on a day one could be a human version of a Ransom Rest.

[Forrest r]

It's not hard to find loads for the 45acp @ 50ft. Nothing more then the usual range scrap I use for +/- 99% of my shooting needs (8/9bhn). I use a lyman m-die for those .452" bullets and mixed range brass.

Those are only 5-shot groups, I'm sure they would open up if I shot my usual 10-shot test groups.

Plan on making a pile of these 4.3gr loads using the mihec 200gr hp and the H&G clone. I'll end up going more testing at longer distances with them. Really all's I was interested in was making a load for the bowling pin table, steel & dueling trees @ 50ft.

The only reason I posted what the results were with the clays loads was to show the op what other people are doing with box stock springfield armory 1911's. Hopefully he will have better success with his reloads after the bbl work is done.

[Nanookofthenorth]

Just to conclude this

I got my barrel back from Doug

Loaded to 1.210 oal and .469 taper crimp

Even with my ****ty powder coating they run great no feeding issues and they shoot great groups.

I tested feeding them into a gen 3 45acp Glock and it got the same malfunction my 1911 was getting before the throat work.

Great work Doug thank you.

[mehavey]

[Broken Record Alert]
Thin film ALOX on the bullet ogive is the great leveler in such chambers.

[DougGuy]

Been thinning the herd and I'm down to 3 molds for the 45acp's/1911 along with selling off all the 1911's except for 2. Both are box stock springfield armory range officers. They are both setup with burris fastfire III's on them.
[IMG][/IMG]

As far as accuracy goes, don't know if there would be much improvement over not having the bbl worked on. I'm the weak link when it comes to the accuracy of these 1911's.

This would make for a very fair comparison of throated vs. non throated. If you read what I wrote about the function of freebore as an alignment tool this facilitates a consistent engagement in the rifling which the abrupt entry into the rifling of the stock barrel cannot accomplish. Those groups you show are good but it wouldn't surprise me to see groups out of the throated barrel tighten to the point that you realize that it wasn't -just- your shooting that determined their size.

[slam45]

i don't know the shape of lee boolits from the numbers... glocks will fight you when running semi wad cutters.. first thing i would try is an AOL of 1.250"... i currently load for 6 45acp's and use that length in all of them with almost any boolit... might have to shorten it a bit if you are running a big flat point ( over 0.28") my G30 will shoot the lights out at 1.25" and 0.469" and run for days with no issues... none of my 45's like them much shorter... these days i run 200 and 230 RNFP with a 0.20" flat point... keep working it you will win... 45acp is among the greatest rounds ever thought up...

i went and looked at the lee 228r1 ...so most of what i said is meaningless with the nose shape of this boolit... I'd get a different mold, as the nose profile of this boolit is going to be more trouble that it is worth... and i don't see how it would powder coat well at all as it is too big in the nose as cast... most likely would work better in a revolver...

Just to conclude this

I got my barrel back from Doug

Loaded to 1.210 oal and .469 taper crimp

Even with my ****ty powder coating they run great no feeding issues and they shoot great groups.

I tested feeding them into a gen 3 45acp Glock and it got the same malfunction my 1911 was getting before the throat work.

Great work Doug thank you.

[Forrest r]

This would make for a very fair comparison of throated vs. non throated. If you read what I wrote about the function of freebore as an alignment tool this facilitates a consistent engagement in the rifling which the abrupt entry into the rifling of the stock barrel cannot accomplish. Those groups you show are good but it wouldn't surprise me to see groups out of the throated barrel tighten to the point that you realize that it wasn't -just- your shooting that determined their size.

Thank you for taking the time to reply doug. I absolutely believe that your quality work would do wonders for accuracy. I just believe my bbl doesn't need it.

Work with me on this 1:

Outside to outside groups need the bullet diameter to be subtracted from them to find the "true" size of the group. Most bullets leave a hole +/- 20/1000th,s" less then the bullet diameter, swc are typically less but I still like to use 20/1000th's. Hence the # .430" for the bullet holes. I have spent a little time over the decades scoring targets, used gauges like these along with calipers to get an idea of what hole a bullet design would leave in paper compared to the bullets diameter. The 44cal gauge is missing, let a guy borrow it and never got it back. Anyway you can use whatever # for what size hole the bullet leaves in the target, whatever your comfortable with.
[IMG][/IMG]

The 3 bullets I used for that test. along with how much the shoulders/full diameter of the bullet sticks out of the case.
[IMG][/IMG]

My bbl measures .906" from the top of the hood to where the step/leade in the chamber begins. Using minus .0002" pin gauges the .451" pin fits into the leade and is tight just before it hits the lands. The .452" pin fits into the leade and will stop +/- 1/2 way to the start of the lands (tapered). Nothing more then the typical bbl springfield puts out.
[IMG][/IMG]

The mihec 200gr hp did a 1" outside to outside group or a true .670" group. It has a 1.25R nose profile & I have to seat that bullet with an oal of 1.180" to get it to feed flawlessly. Seating the bullet that deep means there's no shoulder of the bullet sticking above the rim (see picture above) of the case. It has to jump +/- 10/1000th's align in the leade of the bbl. This bullet should be able to benefit from your bbl work.

The cramer hb swc did a .763" outside to outside group or a true .335" group. That bullets shoulder sticks out +/- 20/1000th's above the top of the case. This puts the .452" bullet's shoulder into the .452" leade of the bbl. There is no freebore with this bullet and it is aligned in the bbl.

The mihec h&g 68 (actually 69) clone is also sized to .452" and has +/- 20/1000th's of the bullet's shoulder sticking above the top of the case. And just like the cramer bullet's .452" shoulder the mihec swc's shoulder is jammed into the .452" tapered leade. And again bullet to bbl alignment. That mihec bullet did a .744" outside to outside group or a true .315" group.

Those swc bullets or any other bullet I use that has the body of the bullet (.452" diameter) sticking above the top of the case +/- 20/1000th's will align/center in the leade of the chamber just like what you're talking about.

At the end of the day if I really wanted to cut down on the group size of the mihec 200gr bullet I'd send the bbl to you. If I wanted to cut down on the group size of the swc's I'd use match brass and a different target. The target I used has a 2" black outer ring and a 1 1/2" white inner circle. The red dots have a 3moa dot which means I'm trying to center a 1/2" dot in a 1 1/2" circle. That leaves the dot centered and a 1/2" circle of white around the red dot. If I switched to a 3/4" or 1" round target that 1/2" red dot would have clearer/easier to judge 1/8" to 1/4" outer ring. I learned for decades of shooting iron sighted target rifles that it's best when using a round sight to have the smallest outer detail ring you can clearly see to center your sight. That's why I end up with a bunch of these for the smaller redfield & lyman sights.
[IMG][/IMG]

And these for the rws, anschutz, 52d, 40x & savage target rifles
[IMG][/IMG]

You say throating the bbl will aid in bullet alignment increasing accuracy.

I say the .452" bullet is already aligning in the .452" leade. That's it's my poor choices in using mixed range brass and the wrong target for testing accuracy.

[DougGuy]

Thank you for taking the time to reply doug. I absolutely believe that your quality work would do wonders for accuracy. I just believe my bbl doesn't need it.

You say throating the bbl will aid in bullet alignment increasing accuracy.

I say the .452" bullet is already aligning in the .452" leade.

Well, can't argue with those groups for one, and for two, you are better off than most getting ANY bit of a .452" proud of the case mouth to plunk with the RO barrels.

Jerry Keefer built the 9mm that won jeez how many matches? .100" parallel freebore and 1 degree leade angle, this school of barrel throating comes with it's own merits, and it's not in your case a "need" as in something won't plunk or fails to feed, but an addition to the barrel geometry that improves by smoothing the path the boolit takes to the rifling. You use a lot of apertures and school yourself on how well the aperture fills the target dot leaving only enough around the edges of the globe for alignment.

My school of barrel throating focuses on the alignment of the boolit between case mouth and rifling. If you think there is no room for improvement then throating the barrel should not improve groups right? Same as switching from plain iron sights to the peep sights? Or is it?

Stock 1911 when it fires, how far does the case expand in the chamber? What is the ID of the case mouth once expanded? Ok now how is this expanded case mouth supporting the sides of the boolit that aren't yet in the "throat?" It's more or less random how the boolit aligns in the throat, this is what the longer freebore removes. It is very close to boolit diameter and is a LOT more precise than the expanded case mouth. It fully supports the boolit between case mouth and leade ins, something which the stock barrel cannot do.

This is what it adds to the barrel, I could get away with reaming throats just enough to get certain style boolits to plunk, you know, customer sends dummy round, I ream the throat tiny bit at a time until the dummy plunks, and then what? How much freebore is in the barrel now? Enough to fully support the bearing surfaces of the boolit? I hardly think so. Jerry Keefer knew this longer throat was not about getting rounds to plunk, he was squeezing every bit of boolit alignment he could get into the barrel itself.

[Forrest r]

Well, can't argue with those groups for one, and for two, you are better off than most getting ANY bit of a .452" proud of the case mouth to plunk with the RO barrels.

Jerry Keefer built the 9mm that won jeez how many matches? .100" parallel freebore and 1 degree leade angle, this school of barrel throating comes with it's own merits, and it's not in your case a "need" as in something won't plunk or fails to feed, but an addition to the barrel geometry that improves by smoothing the path the boolit takes to the rifling. You use a lot of apertures and school yourself on how well the aperture fills the target dot leaving only enough around the edges of the globe for alignment.

My school of barrel throating focuses on the alignment of the boolit between case mouth and rifling. If you think there is no room for improvement then throating the barrel should not improve groups right? Same as switching from plain iron sights to the peep sights? Or is it?

Stock 1911 when it fires, how far does the case expand in the chamber? What is the ID of the case mouth once expanded? Ok now how is this expanded case mouth supporting the sides of the boolit that aren't yet in the "throat?" It's more or less random how the boolit aligns in the throat, this is what the longer freebore removes. It is very close to boolit diameter and is a LOT more precise than the expanded case mouth. It fully supports the boolit between case mouth and leade ins, something which the stock barrel cannot do.

This is what it adds to the barrel, I could get away with reaming throats just enough to get certain style boolits to plunk, you know, customer sends dummy round, I ream the throat tiny bit at a time until the dummy plunks, and then what? How much freebore is in the barrel now? Enough to fully support the bearing surfaces of the boolit? I hardly think so. Jerry Keefer knew this longer throat was not about getting rounds to plunk, he was squeezing every bit of boolit alignment he could get into the barrel itself.

Been saying the same thing in the rimfire section for awhile now in the 50yd br thread. Keep the leade clean/smooth/polished.

Myself I like to use jb bore paste to break the edge where the chamber ends/leade begins (the step edge) and polish the leade and tapered part of the lands.

I also like to treat the locking grooves & bottom lugs with moly after they are broke in. Along with the front of the bbl and bbl bushing. This reduces wear and makes for a consistent lockup shot after shot after shot.

[IMG][/IMG]

So ya, the leade area get hit with 1200grit jb bore paste from time to time to keep it smooth. But I also do maintenance on the outside of the bbl, namely treat for wear.

Anyway that the 1st thing I check is the diameter of the leade of the bbl with a minus pin gauge. If the .452" pin would not of fit I would of simply sized the bullets to .451". As long as the bullet is tightly centered in the leade of the bbl ( .452" bullet in .452" leade/.451" bullet in .451" leade/etc) accuracy will be there as long as the 1911 has consistent ignition & a consistent lockup.

Interestingly enough the springfield ro chambered in 45acp has an extremely short leade with sharp angles on the cuts of the lands which is excellent for accuracy with swc bullets.
[IMG][/IMG]

The springfield ro chambered in 9mm has a long leade and long tapered angles on the cut of the lands.
[IMG][/IMG]

That 9mm bbl extremely well with +/- 2r rn or a rn flat pointed bullet.