Accuracy is coming...

[MemphisMechanic]

How's this looking for GF ... And sorry for the vertical video - hard to film one handed

https://youtu.be/76L8s-UYfBY

Good. That's how mine was fitted - after 800 rounds there's the smallest bit of slop front-to-rear between the barrel hood and the slide cutout. Definitely don't remove any more.

I probably could have fit mine even tighter, and that's how mine was when I finished fitting.

[MemphisMechanic]

Load chronographed at 65* F just before group testing:

135 BBI

3.8gr WST

1.130"

Federal primer

Mixed brass

PF: 133.3

SD: 10.58 (this certainly helped)

(I'm not a phenomenal group shooter, keep that in mind. And yes you're correct, I absolutely need to bag the gun in and see what it can do because the attached photos are not a definitive test.)

Pic 1: A sanctioned IDPA match this weekend includes at least one 30yd target... After 3 years away from run and gun games, what you're looking at is practice for that! This target is 25-30 rounds shot how I'd engage that target with a timer running for score. Previous attempts with the factory barrel always resulted in a couple of Delta hits and at least a half-dozen close Charlies. Ammo selection could possibly be a factor.

Pic 2: Red dot added in paint? That is where I was aiming. This was slow fire, freestyle, unsupported. My gun is sighted to shoot 2-3" high at 25yd. This is a group half the size of anything I've managed with the factory barrel, and includes two called flyers. Group size freestyle was just over 3" without including the flyers - I'm quite happy with the barrel upgrade!

Oh. Apex barrel shot that ammo at 133.3 PF. Switching to the factory 9L 1:18 barrel resulted in a PF of 133.03. So there's practically no velocity change - sample size is small enough I have to treat them as identical. Both barrels are slightly faster than a Glock 34 - search for "chrono" and my username in the 9mm reloading forum for data to back that up.

Edited April 13, 2016 by MemphisMechanic

[ddc]

Sorry if it was clear and I missed it but those targets were at 30 yards?

Also: How do you like your WST load? I've been thinking of trying it.

[MemphisMechanic]

That target was between 20 and 25 yards. This indoor range doesn't have a marking past 20.

To be fully fair and honest I tried a 25yd 6 shot group around a half a dozen times with shotgun-like spreads that steadily tightened up. Once I was satisfied I remembered how to actually hit something at that distance, I shot the groups you see above and they're the absolute best I can manage shooting offhand and fully warmed up.

I left out the previous runs where operator error was making the gun look bad. Very very bad, at first!

Edited April 14, 2016 by MemphisMechanic

[MemphisMechanic]

A 135 BBI coated bullet over 3.8 WST shoots wonderfully. Feels like the ubiquitous 147FMJ over 3.2 titegroup load.

Accurate, clean, and soft.

I just bumped the "WST and 9mm" post back to the top in the 9mm Reloading forum with all of my chronograph data with 124 FMJs and 130 / 135 coated BBIs loaded over WST:

http://www.brianenos.com/forums/index.php?showtopic=185737&view=getnewpost

Edited April 14, 2016 by MemphisMechanic

[ddc]

I've been meaning to pick up some WST. Thanks for the pointer to your other thread.

[MemphisMechanic]

I can't really tell the difference between Clays and WST when they're both loaded to the same PF behind the same bullet.

Considering WST is less smoky and feels a lot like Clays, one of the softest-recoiling powders out there... I have to say I'm happy with WST.

Honestly I feel very little difference between all of the powders in the Titegroup/WST/Ramshot Comp/Solo 1000 neighborhood on the burn rate chart. When powders were cheap and plentiful around 2009 I tried a bunch of recipes in search of the softest "unicorn" load. These days, I find they make almost no difference in your actual performance. So I find an accurate load for my gun that makes about 133 PF and just leave the press setup for it and go shoot!

Edited April 15, 2016 by MemphisMechanic

[ddc]

That's good to know. I've been loading with Silhouette as that was what was available back when I started in the middle of the bad times.

I've been wanting to try a faster powder and have been considering WST, Zip, Titegroup, 231. Sounds like WST might be a good place to start.

[TacticalReload]

Quick question... and I apologize if I'm missing something obvious or if this question has been previously asked and answered.

I realize that there is lost accuracy due to the slop between the OEM barrel at the muzzle and also at the hood. However, it's definitely not rare that service grade pistols have loose fitting parts. Based on everything I've read, seen, and experienced, I'm convinced that the "early unlocking" is the primary culprit for a bulk of the poor accuracy (and that sloppy fit just makes it exponentially worse -- which is why I think that some guns exhibit very poor accuracy while others are just mediocre and still others are acceptable).

So, why wouldn't it be possible to build up either the OEM barrel lug (in the same way that the Apex barrel has the fitting pad) or possibly the locking block (unless this adversely affects the geometry of other parts of cycling) by welding up material on those parts? If this could prevent the barrel from fully unlocking as early, it might improve accuracy considerably -- even if it doesn't get anywhere near the absolute accuracy of the Apex barrel.

If this works, it could give an option to people who are trying to use a threaded or conversion barrel or who are experiencing accuracy issues with .40 or .45 guns... at least until (and if) Apex starts producing these versions. Thoughts? If I had the equipment needed to do something like this, I would probably give it a try to see how it works with a spare OEM barrel or locking block.

Edited April 23, 2016 by TacticalReload

[mpeltier]

Quick question... and I apologize if I'm missing something obvious or if this question has been previously asked and answered.

I realize that there is lost accuracy due to the slop between the OEM barrel at the muzzle and also at the hood. However, it's definitely not rare that service grade pistols have loose fitting parts. Based on everything I've read, seen, and experienced, I'm convinced that the "early unlocking" is the primary culprit for a bulk of the poor accuracy (and that sloppy fit just makes it exponentially worse -- which is why I think that some guns exhibit very poor accuracy while others are just mediocre and still others are acceptable).

So, why wouldn't it be possible to build up either the OEM barrel lug (in the same way that the Apex barrel has the fitting pad) or possibly the locking block (unless this adversely affects the geometry of other parts of cycling) by welding up material on those parts? If this could prevent the barrel from fully unlocking as early, it might improve accuracy considerably -- even if it doesn't get anywhere near the absolute accuracy of the Apex barrel.

If this works, it could give an option to people who are trying to use a threaded or conversion barrel or who are experiencing accuracy issues with .40 or .45 guns... at least until (and if) Apex starts producing these versions. Thoughts? If I had the equipment needed to do something like this, I would probably give it a try to see how it works with a spare OEM barrel or locking block.

You may get a slight accuracy benefit by tightening up those areas, but I believe that the biggest detriment to accuracy with the factory bbls is the position of the ramp that cams the bbl down as the slide moves backward. This picture illustrates well that the APEX bbls ramp is considerably farther forward and at a slightly different angle than the factory barrels ramp.

oops, after re-reading your post we may be talking about the same thing. My feeling is that for the cost of the APEX bbl it would take a lot of work, if even possible to get even close to the APEX bbl.

Edited April 25, 2016 by mpeltier

[TacticalReload]

I did a side-by-side comparison after I posted, and I do see the major points of difference between the two... I tend to agree that it would be pretty difficult. The lugs really aren't all that similar in geometry to warrant modifying the factory barrel over simply buying the Apex.

[Art Yeo]

Increase the shooting distance

I would like to see the groupings for various test results shooting at 25 yards and 50 yards by hand on sandbags.

If any of you have the drop-in Apex bbl, let's see the groupings as well.

And, let's shoot it with heavier loads 9mm. Light loads used for competition is not the norm for 9mm. The Army Marksmanship Unit had tested the 9mm to death and the most accurate loads are the heavier loads.

As I have reported previously on this website, at close range, you cannot see much difference among all the bbl (Old style OEM , New style OEM, Storm Lake, etc.)

You can only see the difference when you increase the distance.

So, let's see those.

Randy,

If you have test results that meet the above requirements, please post them.

Also, if you can comment a little on why you changed the twist rate to 1:10, if would be great.

Edited April 27, 2016 by Art Yeo

[rhowell309]

Art, there is a similar thread where I posted something like this. 25 yards, 115g Blazer Brass and 124g match ammo that is not light, shot from a ransom rest, and with both stock and APEX barrels.

That thread was updated today and it was post 57. I can't link it on the road with tapatalk right now. Or search for posts on my username.

I'll be glad to repeat it with any factory ammo you desire if you'll provide it. 50 rounds of each would be preferred as I now have two 5" pistols with stock and APEX barrels. That is one is pending return from APEX that was used in the test. The one is the newer version of the barrel and is functioning flawlessly, but I have not shot it on the rest yet.

[DougM]

Art:

I believe the thread rhowell is referring to is at http://www.brianenos.com/forums/index.php?showtopic=231134&page=3. It is entitled "Accuracy - What would you do?" in this M&P forum.

[rhowell309]

Art:

I believe the thread rhowell is referring to is at http://www.brianenos.com/forums/index.php?showtopic=231134&page=3. It is entitled "Accuracy - What would you do?" in this M&P forum.

That's it. Thanks for linking it.

[Titaniumbadger22]

I shot my M&P Pro with the SDI barrel today. It functioned perfectly, but I had an unusual spread. 5 Shot groups from 25 yards, Vertical spread was 4", horizontal spread was 1". For comparison, my CZ shot a 2" group and my RIA shot a 3" group with the same ammo. If I could reduce the vertical spread to match the horizontal, I would be very happy.

When I fit it, I took a lot of material off the back and not near as much off the lugs on the bottom. I didn't want to go do far, but maybe my gun is too tight and not consistently pushing the barrel into the same position? If I slingshot the slide from full back it will fully go into battery, but any less it requires a nudge to get it to go. I shot about 100 rounds through it today and had no misfires or feed failures.

I'm thinking I need to remove more material, but I'm not sure if I should go after the back some more or the bottom lug?

Anyone else have this issue?

Edited April 29, 2016 by Titaniumbadger22

[TacticalReload]

Weird. I wouldn't take any more off the fitting pad / lug area without figuring out what's going on first. The "nudge" you describe seems like the right fit as per Randy (and will probably start to go away after enough rounds wear the barrel in).

By any chance, do you have barrel springing? When you have the slide off the gun upside down and you're trying to get the hood to drop into and lockup with the slide, does it require enough force that you're slightly bending the barrel to get it fully in -- and then does it slightly pop back out when the pressure is released? Or does it just drop in completely and cleanly without any tension and stay in place on its own?

[Titaniumbadger22]

Now that I'm playing with it, it does have spring to it. With the barrel in the slide and the slide upside down, I have to push it to get it to go all the way down. It looks like the front of the barrel is putting tension on the barrel. I been staring at trying to figure out if it would be better to take a little off the top or the bottom of the front of the barrel. It looks like if I took a little off the bottom very near the end and a little off the top about 1/4" from the end to the end of the lug might help.

Have you seen this issue?

[TacticalReload]

Now that I'm playing with it, it does have spring to it. With the barrel in the slide and the slide upside down, I have to push it to get it to go all the way down. It looks like the front of the barrel is putting tension on the barrel. I been staring at trying to figure out if it would be better to take a little off the top or the bottom of the front of the barrel. It looks like if I took a little off the bottom very near the end and a little off the top about 1/4" from the end to the end of the lug might help.

Have you seen this issue?

Yep... it's what was happening with mine. That's how I knew to suggest it... it's also why I suggested that you not take any more off the lug. I used a sharpie to find the contact points on the barrel (poor man's dykem). I took a little off the top and a little off the bottom VERY slowly until the springing was gone. I'm guessing you probably could just take it all off one place and still be fine; but I did both so I could cut the difference in half instead of going too deep in one spot. (I didn't want to cause any functioning problems with an irregular barrel profile.)

No guarantee that it will solve your vertical stringing problem, but it's one of the first things I look for in 1911's when I see it.

[Titaniumbadger22]

Thanks for the help! It all makes sense to me. After shooting it today, there are wear marks on the top and bottom, I'm guessing that would be a good place to start.

[TacticalReload]

Out of curiosity, what kind of groups were you shooting with the factory barrel?

[mpeltier]

Increase the shooting distance

I would like to see the groupings for various test results shooting at 25 yards and 50 yards by hand on sandbags.

If any of you have the drop-in Apex bbl, let's see the groupings as well.

And, let's shoot it with heavier loads 9mm. Light loads used for competition is not the norm for 9mm. The Army Marksmanship Unit had tested the 9mm to death and the most accurate loads are the heavier loads.

As I have reported previously on this website, at close range, you cannot see much difference among all the bbl (Old style OEM , New style OEM, Storm Lake, etc.)

You can only see the difference when you increase the distance.

So, let's see those.

Randy,

If you have test results that meet the above requirements, please post them.

Also, if you can comment a little on why you changed the twist rate to 1:10, if would be great.

OK Art,

Went out to my range today to do some longer range shooting with my M&P 9L with both the Apex SDI and the factory ported barrel. The only factory ammo I had was a box of Winchester Ranger 127gr XST and a box of Federal 147. The factory barrel preferred the 147 and the Apex liked the 127, so thats what I grouped each with. The Apex barrel only shot groups a little larger with the 147's at 50yds but the factory bbl did not like the 127's at all, shooting groups of 10-12" at 50 yds. I was extremely pleased with the Apex bbl. The Factory barrel is not horrible, It is the best of the five M&P's Ive owned.

[want2race]

Fit mine. It's tight and it's right. LOL. I stopped removing material when it was close and lapped in by hand. Then also polished the top of the locking block a little. They are pretty rough. First session when pretty well. I may Ransom it later, but this is promising.

[Titaniumbadger22]

I didn't get a controlled group to measure against before I changed barrels. I think after I get mine seated properly I'll go back out and get results with my stock barrel and the SDI.

Edited April 30, 2016 by Titaniumbadger22