9mm accuracy suggestions

[Williamb]

Been actively reloading for more than 10 years; however, first time with the 9mm.

Been using the following:

• starline brass
• MG 124 HP
• N320 4.1 GRAINS
• CCi SMALL PISTOL PRIMERS
• oal 1.13
• m&p 9 4.25" BARREL

I HAD STARTED WITH 3.9 - 4.1 AND THEN 4.3 GRAINS. I ENDED UP WITH 4.1 GRAINS AS BEING THE MOST ACCURATE OF THE 3 TRIED. HOWEVER WHEN I SHOOT FACTORY American Eagle 115GR FMJ accuracy is much better. With the 115 gr I can usually put a clip of 17 into a 1.5" group at 15 yards with this pistol. Shooting the 124 MG with 4.1 grains of 320 the groups are 3 t o 4 inches at 15 yards.

Any suggestions on tightening up these groups using the components I have would be appreciated. Also I would be interested in hearing what groups others are shooting with these components with the M&P9.

Thanks

Edited September 12, 2013 by Williamb

[Yagi]

I have the same load but it gives me 1-1.5" group at 25 yards benched if i really do my part...

[Williamb]

I have the same load but it gives me 1-1.5" group at 25 yards benched if i really do my part...

Really same everything OAL - pistol - etc. This was not benched I was shooting standing. With my 45 and hand loads I can shoot one ragged hole standing so this is usually how I test loads. If everything is the same I will go back to the range. Maybe I was just having an off day. I will also do it off the bench.

Thanks,

Will

[bikerburgess]

I would play with crimp and OAL to find what works best in your pistol.

[Williamb]

I figured OAL is the deal on this. Don't really want to decrease the OAL without decreasing the load and working up again looking for pressure signs. Looked at my carry ammo which is 124 gr speer gold dot. OAL is 1.1185 even though the speer manual calls out 1.12. Lots of variables.

Edited September 12, 2013 by Williamb

[njl]

I never was happy with MG 124gr JHP accuracy until I went really short on the OAL. Try closer to 1.10", and I agree, you should work back up at that OAL. I use a very mild load, and shortening it bumped the velocity up from sub to supersonic. I don't "know" VV powders, so I have no idea where you are in the load range.

[rhyrlik]

Try 1.050" OAL.

9mm's prefer a short OAL with a TC profile bullet.

[Justsomeguy]

Like rhyrlik indicated, the 9mm is somewhat picky about OAL with different bullet types. You don't want to be right into the lands with a short cased round like the 9mm, and TC bullets are more prone to hitting the lands because of their shape. In general, every .01 reduction in OAL requires about .2grn powder reduction with medium speed powders. 320 is a bit faster so you might want to start .3grn lower and see what it gets you.

[Williamb]

I have read a number of threads which have stated that 124 gr MG JHPs like to be loaded short. I have also read that a popular loading with this particular bullet is 4.0 - 4.1 grn of N320. However, I have not seen the combination of both a (short) OAL of 1.050 along with N320 of say 4.1 grn.

I would assume that if both are accurate separately that they might have been combined together. My initial concern might be compression problems with the powder and a pressure spike. Is my assumption correct or have I missed something? If anyone has used this combination of a short OAL with N320 what were the results. Alternatively does anyone know of a loading with N320 and a short OAL that proved to be very accurate in your pistol. Not trying to avoid working up a load just trying to look for pointers of places to start.

Thanks

[wes777]

Just a thought, your barrel likes 115s, why not feed it 115s? Best guess is that the concentricity of your reloads may not be cooresponding well with a factory barrel designed around reliability, ie, looser tolerances. However, even with a tight chamber, it may not ever shoot the 124s well. I get better accuracy out of the hornady 124s than with the Montana golds.

-last note, i spoke with several of the wizards at the AMU service pistol

/ bullseye team. They are using 115s exclusively. After alot of testing, 115s were the only weight bullet that was stabilizing enough to keep sub 1" at 50 yards. 147s did well out of a 1911 barrel, but that was the only exception. I realize that we are talking about completely different guns.... 115s are just good in 9mm.

[Williamb]

Hornady XTP bullets have an excellent reputation for accuracy but I think that they are almost double the price of the MGs - so for range shooting the MGs are ok for me. I'm not sure that my barrel does not like 124s. My carry load is Speer GDs 124 gr and they shoot great. Just can't afford to burn through them as I would with MGs.

Does anyone know of a load with N320 and a short OAL that proved to be very accurate in your pistol. Not trying to avoid working up a load just trying to look for pointers of places to start.

Thanks -

[Williamb]

Someone must have a load that they think to be accurate using N320 @ 125 gr MG JHPs with a short (less than 1.13) OAL.

[njl]

Just load up a couple of small test batches (~20 rounds each) with 4gr N320 at 1.050", 1.100", and 1.120". Test them for accuracy and chrono them, working from the longest to the shortest, and let us know what happens. If the velocity gets scary, stop.

[Williamb]

Just load up a couple of small test batches (~20 rounds each) with 4gr N320 at 1.050", 1.100", and 1.120". Test them for accuracy and chrono them, working from the longest to the shortest, and let us know what happens. If the velocity gets scary, stop.

Thanks - I'll be at the range tomorrow. All loaded and ready to go. By the way I stumbled upon some of Darrell's posts. They were extremely helpful.

[CZ85Combat]

I think you will find that 1.050 will be a compressed load. With 4.0gn N320 at 1.080 you will get about 1050fps. I ran 124gn MG, N320 3.9gn At 1.085oal in my CZ85 Combat with 129pf with 1.5" groups at 25yards

Edited September 17, 2013 by CZ85Combat

[Williamb]

I think you will find that 1.050 will be a compressed load. With 4.0gn N320 at 1.080 you will get about 1050fps. I ran 124gn MG, N320 3.9gn At 1.085oal in my CZ85 Combat with 129pf with 1.5" groups at 25yards

Thanks for the suggestions. I was going to the range today but had to put it off until tomorrow. Bringing my chronograph and will stop testing if the velocity gets out of hand. I would find 1.5" @ 25 yrds more than acceptable.

[Red Ryder]

Someone must have a load that they think to be accurate using N320 @ 125 gr MG JHPs with a short (less than 1.13) OAL.

4.2 to 4.3 grains of N320 1.135 OAL .376-.378 crimp, 124 gr MG JHP. Good luck!

[Williamb]

Well got back from the range a few hours ago. Had a great day; however, a little disappointing with working up a useful load for accuracy. This was my second trip to the range for the 9. The first trip I decided that 4.1 grains of N320 was the most accurate; however, I came to that conclusion possible erroneously as for a given OAL of 1.135 I had tried 3.9 - 4.1 - and 4.3 grains and concluded that 4.1 grns was the more accurate of the 3.

Today using 4.1 grns of N320 I had cartridges with OALs of 1.155 - 1.145 - 1.135 -1.125 -1.115 and 1.105. I was concerned with going shorter than this as I was trying to avoid any type of pressure spike having not much experience with 9mm load development. Well using my chronograph easily showed that even at the shortest OAL my velocity was only 977 with a SD of 12 - well within limits.

I'm now thinking about two alternatives for my next trip to the range. I can continue with my present process of loading 4.1 grains and go with cartridges 1.095 and 1.085 or I can start from the beginning again which might be more productive. I believe I read a post by Darrell where he suggested to use the longest OAL and then have loadings reduced by .10 of a grain to determine which powder weight works best with that OAL. Once determined you then develop loads using that weight and decrease OALs by .01 until you find an accurately load.

Since dragging out the chronograph is a bit of a pain I think I will do both exercises so I don't have second thoughts.

Any thoughts on my planned methodology would be appreciated. I am also looking to try Power Pistol but as of now can't seem to find any.

Thanks for the interest.

Edited September 17, 2013 by Williamb

[njl]

977fps is kind of slow for a 124gr bullet. I just noticed, you didn't mention the velocity (or if you'd chronographed) with your original loads. Did you find the OAL (going shorter) had any effect on accuracy? If you're not shooting anything where PF matters, I guess being sub 1000fps doesn't matter. Otherwise, you'll need to get that up into at least the 1025-1075fps range.

[Williamb]

977fps is kind of slow for a 124gr bullet. I just noticed, you didn't mention the velocity (or if you'd chronographed) with your original loads. Did you find the OAL (going shorter) had any effect on accuracy? If you're not shooting anything where PF matters, I guess being sub 1000fps doesn't matter. Otherwise, you'll need to get that up into at least the 1025-1075fps range.

I did chronograph all:

1.155 - 942 18sd

1.145 - 946 12sd

1.135 - 954 10sd

1.125 - 974 18sd

1.115 - 977 12sd

1.105 - 989 16sd

I would agree all very soft. The 1.145 OALs gave me the best group. At 15 yards they were 1.5" off the bags. Even though I planned too I didn't bother trying at 25 yards as the result at 15 yrds was unacceptable.

From what I have read to get accuracy out of the MGs JHP you need to push them over 1050 and reduce the OAL even more than I have done.

To answer your question going shorter seemed to improve things a bit but difficult to really know. With 5 shot groups I was getting two holes touching then maybe 1.5 to 2 inches away I would get another 2 holes touching and there generally was a hole apart from these. This sole hole was probably the first round of a new magazine - that's my guess. I need the shots to tighten up. This was all at 15 yards.

I think I can actually shoot better freestanding as compared to off the bench. I rarely shoot pistols off the bench. I'm even thinking about using a Ransom Rest however our club does not have cement benches but wooden ones which will not be as secure a base. Oh well the trials of having fun

[DWFAN]

1.5 inches may be all that gun is capable of. 2-3 inches at 25 yards isnt too bad for a service pistol.

Switch to a Zero bullet and your groups may shrink.

[Williamb]

1.5 inches may be all that gun is capable of. 2-3 inches at 25 yards isnt too bad for a service pistol.

Switch to a Zero bullet and your groups may shrink.

You are absolutely right. M&Ps are not known to be as accurate as some others. Believe Smith actually updated the barrels awhile back. Compared to the accuracy of my 1911 the M&P is forgettable. Was consider putting a Barsto through Apex tactical in but they are about a year past due for delivery.

Once I figure out an acceptable load I don't think I will put anymore money into it. I have already put all the bells and whistles that Apex Tactical into it. The trigger is actually very good now compared to stock.

I think money better spent on a custom target shadow. I know the accuracy is there and it looks like its ready to go from the get go.

In any case I will spend more time on load development. I enjoy reloading when it pays off in improved accuracy.

[RH45]

My pistols have never shot very accurate with MG bullets, and they have also been the slowest at the chrono.

Nosler jhps and XTPs are at the top of my list for accuracy, but, too expensive for me. Zero jhps are really close, and I used them exclusively for a Looong time, but, availability the last several years sucks, and even though they aren't a pretty bullet, Precision Delta 124 jhps are shooting 3" groups at 100 yards out of several of my guns, so that is what I've been using the last couple of years.

BTW: 4.1 of 320, behind a Zero .356, 125 jhp, was my standard IDPA, and Production load, and always chronoed around 1050 fps, out of my 5" guns.

[Williamb]

BTW: 4.1 of 320, behind a Zero .356, 125 jhp, was my standard IDPA, and Production load, and always chronoed around 1050

What was your OAL?

PD is on my want list. They seem to be back ordered for quite awhile.

thanks

Edited September 18, 2013 by Williamb

[Justsomeguy]

With the possible exception of 147grn bullets in 9mm, most of my testing has indicated that other bullet weights seem to like to "go fast" to give good accuracy. With 124's in XD types and EAA guns MG JHP's seem to like it at or over 1100fps. I have no data on M&P guns myself, but have read and heard that they are not as accurate as some others in stock condition. Still... try getting the bullets moving a bit faster and things might improve. Barrel twist rates have been altered lately by some manufacturers and this could also be a factor.