Oal On Montana Gold Bullets

[markwilliston]

Hey everyone,

I'm shooting IPSC with an STI trojan 5.0 in .45ACP been having problems with failure to feed with both 185JHP and 200JFN from Montana Gold. Using Chip McCormick 10 round powermags, more often than I care for the first round dives instead of climbing the ramp. Gunsmith suggested that I had the bullets seated to deep.

Anybody else have problems? Or suggestions for an OAL that'll work with these bullets?

Mark

[Mick]

I try to reload my .45s as long as possible to avoid feeding problems like you mentioned. I also put in an SV mag catch that is .030" taller to help get the rounds started. I also had problems with the McC. 10 rounders and switched to Wilson 10 round mags...no further problems...

I started using the Precision Bullets 230 grain RN over 4 grains of Clays for about 760 fps which is a little strong but shoots great...

Mick

A27257

[LPatterson]

You didn't say what your OAL length was but in a Wilson & Schuemann barrel 1.220 worked well for me.

[Carlos]

Had big problems w/ the Montana Gold 200 grn flat nose (sort of a .45 "soft point"); I loaded them to 1.240 - which was well w/in the Minimum/maximum OAL for .45 and the 200 grn jacketed bullet. That bullet not only touched the rifling in my .45, it would not let the round fully chamber at that length. I used them up in my 625 (a .45 ACP revolver). Shot great in that gun. However, watch out for that bullet in an autoloader. It is NOT interchangeable w/ a SWC or a RN of similar weight as far as OAL.

Edited November 27, 2006 by Carlos

[38superman]

I really like the MG 200 fp bullet.

It is one of the more accurate bullets I have tried in my 45's.

It feeds just fine in my Springfield but is not 100 % reliable in my STI Edge.

In my experience the problems you describe often turn out to be magazine related rather than OAL issues.

Number your magazines and note which magazine is in the gun when the problem occurs.

You may be surprised to find that when the gun fails to feed it's with one or two specific mags.

If the magazine is a little out of tolerance it may not seat high enough to reliably feed the bullet.

I had a similar problem with a Para P14 and with my STI Edge.

Drove me crazy because the gun would feed great when I was shooting off the bench but couldn't make it through one stage in the field.

Burned up a lot of components playing with OAL etc before I found the problem.

I had one magazine that wasn't seating deep enough.

On the bench with the grip resting on a sandbag it pushed up on the magazine and no problem.

In the field with the mag unsupported, consistent malfunction.

Tony

Edited November 29, 2006 by tlshores

[markwilliston]

The OAL I was using for them is 1.195 which appears to be on the short side. The Chip McCormick mags have the bullets in the magazine at a shallower angle than the 8 round mag that came with the gun from STI. The gunsmith is Joe Dlask, and we put one of his mag catches which I think he said was .020 taller or something like that.

When I took it to his shop, I brought along all my magazines and some primerless rounds. Sure enough he showed me that I had two magazines with a lot more play than the others. I will number them and see how it goes from there.

[markwilliston]

Just tried it out today with the bullets set at 1.225 and it worked great!

Now my 550 can go into overdrive while the weather outside it crummy.

[superdude]

gosh, i just posted this on another link literally a couple seconds ago, so i will include it here as well. it helps to understand why the nose dive thing occurs in the first place.

round nose bullets will help reduce the problem because the bullet nose hits the feed ramp a little higher.

okay, here is a copy of a previous posting.

Ah yes, the famous, or infamous, nose dive feed failure.

The phenomena you described is well known. The more rounds you load, the greater the change of angle in the top round. A noticeable change in angle occurs after there are about 4 rounds in the mag. I’ve spent many hours loading and measuring mags of various sorts, and all the mags I’ve measured thus far suffer from the same problem, but the effect is rather pronounced in 1911 single stack mags. I hope to write an article on this matter, with the hope it will be published in a gun mag or at least on the web. I’m working on a website for the 38 Super and that information will end up there in some form at some point (www.38super.net - sorry, but its free advertising!)

You’re right that the effect is more pronounced with tapered cases like the 9mm. but the problem still exists with straight walled cases like the 38 super.

The cause of the changed angle is a little tough to figure out. The angle of the follower changes, but its not obvious why. Some folks have speculated about the magazine spring and laws of physics and all that – which I didn’t understand but I’m not all that bright when it comes to anything involving math.

I suspect that the rather unique configuration of the Chip McCormick follower is an attempt to correct this change of angle to some degree. It might help a little, but in the final analysis the top round still nose dives.

This problem plagues 45 single stack mags to no end. This might explain why some manufacturers market 45 mags that hold only 7 rounds and other manufacturers sell ones that hold 8. The feeding reliability with 8 rounds is a genuine concern. (Putting in that 8th round dramatically changes the angle of the top round, and it nose dives terribly. It’s the same thing with 10 round mags for the 45 single stack.)

For example, I have an aluminum frame single stack cut for a ramped barrel that I put a 45 top end on. When I load a mag with 8 rounds and the top round is a hollow point, it can nose dive so far that the edge of the hollow point bullet actually hits the aluminum frame below the barrel’s feed ramp – it has the scars to prove it – and of course the cartridge stops dead. With only 7 rounds in the mag it behaves better and only rarely jams. With 6 rounds in the mag it runs fine. You can get around that with loading hardball rounds as the top rounds, but that’s not quite what I want to put in this gun because its for self defense. Oh, and even the proprietary Pow’RBall round nose will jam there – I tested that hypothesis. And by the way, all mags act that way, Colt, Springfield, CMC, Wilson Combat. It’s a chronic problem, and the folks at EGW pointed that out to me.

I converted the gun to 38 Super and the problem went away. It still nose dives with a full 10 round mag, but it doesn’t dip as far because the center of the bullet is much higher than a 45 and the bullet always hits the feed ramp (so far!).

So, how is the problem fixed? It does not look like there is a magic bullet (sorry about that terrible pun) to fix the nose dive angle problem. From what I’ve read it has been tried. (but feel free to invent a better mouse trap! You will be adored by millions!) The only advise I can give is to polish the inside of the magazine lips where it contacts the case and its rim. This will allow the round to move forward a little easier (less friction) and will reduce the tendency to nose dive. And round nose bullets will make the contact point on the feed ramp a little higher, but from what I understand its hard to find 40 caliber round nose bullets.

Also remember that as you put more rounds in the magazine the spring pushes back all the harder and causes more friction between the top round and the inner feed lips. This only makes the problem worse.

Rest assured that you do not suffer alone. Lots of shooters are pulling their hair out because the top rounds nose dive and stops dead. Well smoothed feed lips – read well used feed lips – and well used brass – they gets smoother with tumbling and polishing – the problem is less frequent.

Hope this helps.

[para45]

You may want to chrono that now that you changed the OAL before you go nuts and load a bunch that may not make major. Take care, John

[markwilliston]

Superdude, thanks that was pretty interesting comments. Re the nosedive, different bullets do act differently. I put probably 2500 lswc bullets through my gun with the same 10 round CMC mags. No nosedive probs, but the Lswc has the same ogival radius as the round nose.

Another wise birdy that I shoot with that used to shoot .45 alot suggested tweaking the mag springs ever so slightly to it is shapped sorta like a banana. This makes the follower sit at a steeper angle, and the bullet is more likely to go up the ramp then dive.

Lets see what I get for reliability with it after a bunch of rounds have gone through the gun :-)

Para, ya I downloaded to practice loads to start with and that is what I tested. I'll set things up for match ammo once everything is more stable.

This last year being my first year, I never ever caught up on reloading. At 10pm the night before our provincial championships I was loading.... when I should have been sleeping. Not this year :-)

I really do enjoy the amount of experience available on this forum.

[superdude]

bullet construction and profile can make a huge difference in how the nose dive affects feeding. cast bullets are made of a hard lead allow and have a tendancy to feed well. swaged lead bullets are made of a softer material and are more likely to have feeding issues, and the same is true of plated bullets because their lead core is usually rather soft - and this is more likely to happen in 45 ACP than 38 super because the Super (and 40 caliber rounds) sit higher in the magazine (simply because they are smaller diameter) and hit the feed ramp in a higher point than the bigger rounds.

[MichiganShootist]

I burned through 10K rounds of .45 in two single stacks last season with ZERO nose dives... so my advice is short and sweet.

1 Use Wilson Mags. Their follower tips less than all the others I've tried

2 Load .45s to 1.24 - 1.25 in OAL (They WILL feed better... when longer in many guns)

3 Several of the match grade 45s that I have needed to have the chamber reemed (just a little) to feed 100%

4 Stick with 230 grain FMJs 100% of the time.

5 Clean mags. (entirely) often and replace springs often

6 Polish the feed ramp and chamber every time you clean your pistol

Good Luck

Edited January 9, 2007 by MichiganShootist