Higher than expected velocities with BE-86

[BiknSwans]

I’ve been getting higher than expected speeds using BE-86. I’m using an M&P Pro, which has a 5 inch barrel and using a Caldwell chrono. For my latest load, I wanted to go to a reasonably high power factor. I want to use these rounds as a practice round that approaches major (165 power factor), but safely. I have been shooting .40 S&W at USPSA matches, in Limited Major, but it will be less expensive to shoot 9mm in practice. And I’m not good enough to worry too much about shooting exactly the same round in practice and matches.

For the 124 grain Acme, OAL 1.125 I got the following:

grains speed PF

4.5 1047 130
4.7 1100 136
4.9 1142 142
5.1 1173 145

Load data at Alliant’s website for 125 gr lead RN, 1.120” OAL, 4 inch test barrel, 5.7 grains BE-86 yields 1,179 fps. Power factor is 146. This data most closely matches my load.

I’m getting about the same power factor at 5.1 grains as Alliant does at 5.7. I think I’ll stop at 5.1 for now. I don’t feel comfortable exceeding the maximum power factor that Alliant data indicates.

I reviewed all the 9mm data for BE-86 at Alliant’s website, and the maximum power factor for 8 different bullets ranged from 140 to 150.

I have been loading for about 5 years now, and have always gotten speeds that were about what I expected. I have checked my electronic powder scale (Frankford Arsenal) against a beam scale and a friend's more expensive electronic one and they were in agreement. I’ve also checked my chrono, a Caldwell, against the same friend's LabRadar, and they agreed. I also got higher than expected speeds loading Precision 147s and Acme 145s in earlier testing. In fact, I got a power factor of 156 using the Acme 145s over 4.5 grains of BE-86.

Have any of you noticed a higher than expected velocity using BE-86?

Can a one inch longer barrel make that much difference?

My only theory right now is that BE-86 is slower than some of the other powders I’ve used and is still at a decent pressure when the bullet is in the last inch of the barrel, giving the bullet an additional speed boost.

 

[Fine Figure of a Man]

The extra inch of barrel could give you 50 fps and coated bullets shoot faster than plated or lead with the same charge, in my experience.

 

[Sunray]

The "power factor" is an arbitrary shooting game number that has nothing whatever to do with reloading. Any 'power factor' number is totally irrelevant. There's absolutely no point in shooting one pistol for practice then another in a match either.
5.1 grains of BE-86 is the Max load for a 147 grain jacketed bullet. Nothing to do with a cast 124/125(one grain won't make any difference.). The Max load for a cast 125 at 1179 fps is 5.7. The start load for a cast 125 is 5.1 of BE-86, not 4.5. That'd be Max less 10%.
Do not just pick a load and hope. You must work up the load.

 

[wally]

There's absolutely no point in shooting one pistol for practice then another in a match either.

Maybe not for sponsored shooters but I can think of several reasons for "normal" shooters to do so -- economy 9mm bullets cost less than .40S&W, cheaper ammo usually means more practice -- brass availability, at our club its hard to come back with less 9mm brass than you shot, not so for .40 or .45 -- less wear and tear on your match gun and your joints if you are getting older.

 

[Dudedog]

I think Alliants data for BE86 tends to run on the hot side. I have never went to the MAX load they list.
4.7 was giving me around 1100, 4.3 around 1000. Pretty close to your numbers and higher than I would expect.
Alliants 5.7 as a MAX with lead, 5.9 as a MAX with Jacketed.
Here are some #s from a 5" 9mm 1911 RMR 124 FN @ 1.09 S+B SP
String: 5
Date: 7/23/2016
Time: 9:30:43 AM
Grains: 124
Hi Vel: 1003
Low Vel: 957
Ave Vel: 974
Ext Spread: 46
Std Dev: 18
RMR 124 FN 4.3 BE86 1.09 OAL
Velocity Power Factor Ft/Lbs
957 118.668 252.143
960 119.04 253.726
983 121.892 266.03
1003 124.372 276.965
969 120.156 258.506


String: 6
Date: 7/23/2016
Time: 9:34:47 AM
Grains: 124
Hi Vel: 1116
Low Vel: 1057
Ave Vel: 1092
Ext Spread: 59
Std Dev: 23
RMR 124 FN 4.7 BE86 1.09i OAL
Velocity Power Factor Ft/Lbs
1090 135.16 327.097
1116 138.384 342.888
1089 135.036 326.497
1110 137.64 339.21
1057 131.068 307.591

 

[BiknSwans]

Thanks everyone. I will take the same approach as Dudedog and stay well below Alliant's maximum load. I feel more comfortable after seeing good agreement with Dudedog's data too. I may continue working up the load a little at a later date, but 1173 fps is fast enough for my purposes right now.

I should have mentioned that I'm using the same M&P frame and just swapping slides when changing calibers, so the feel is very similar shooting either caliber. I only have the Apex flat faced trigger, which I love, installed on one of my two M&Ps. I can also swap in a Storm Lake .40 S&W to 9mm conversion barrel and appropriate recoil spring to change to 9mm.

Thanks again. I've really enjoy following this forum. There is an incredible amount of information available here, and it's helped me a lot.

 

[Dudedog]

PS:
Welcome to THR, lots of great people here.

I did some later testing with a different lots of BE86 and my numbers ran a little lower. I will see if I can did them up.
If you figure in the allowed 5% (10%?) difference in lots it could just be the lots we had (have) were on the hot side of the allowed range.

 

[Rock185]

Hello Bikn, haven't used BE-86 but have been reloading since '67. Yes, an inch longer barrel makes a difference, and will sometimes add a 100 FPS. Sometimes though, a longer barrel is slower than a shorter barrel. For instance, I have a couple S&W 9MMs. The one with the half inch shorter barrel consistently records higher velocities than the gun with the longer barrel. Any powder may give higher or lower velocities than the guide indicates since our personal guns were not used to generate the results shown in the book. Even same model guns, by the same manufacturer, will sometimes demonstrate significantly different velocities. Lately, I've been loading 38 Super and Super Comp. Without exceeding max loads as shown in the manual, my guns will often produce velocities 100+ FPS faster than shown in the manual. I don't have a crystal ball where reloading is concerned, so I depend on my chronograph for real world data.............ymmv

 

[Hokie_PhD]

Hello Bikn, haven't used BE-86 but have been reloading since '67. Yes, an inch longer barrel makes a difference, and will sometimes add a 100 FPS. Sometimes though, a longer barrel is slower than a shorter barrel. For instance, I have a couple S&W 9MMs. The one with the half inch shorter barrel consistently records higher velocities than the gun with the longer barrel. Any powder may give higher or lower velocities than the guide indicates since our personal guns were not used to generate the results shown in the book. Even same model guns, by the same manufacturer, will sometimes demonstrate significantly different velocities. Lately, I've been loading 38 Super and Super Comp. Without exceeding max loads as shown in the manual, my guns will often produce velocities 100+ FPS faster than shown in the manual. I don't have a crystal ball where reloading is concerned, so I depend on my chronograph for real world data.............ymmv

Can you explain how this happens? Is it due to twist rate? Design? Something else? I ask to learn and also as I'm now very curious

 

[eo1bart]

Your velocities sound about right based on my experiences. I've loaded a lot 124gr lead, FMJ and JHP bullets from various manufactures in the past year using BE-86. My current load for steel challenge is 4.7 gr under a 122gr Acme FP bullet. Here's the data from my Caldwell chrono from when I was working up that load;

Beretta 92FS-4.9" Barrel
4.4 1015 fps
4.6 1050 fps
4.8 1090 fps

 

[Walkalong]

Can you explain how this happens?

Nope.

I have a 6" M-14 .38 Spl that shoots the same speed as a 4" M-10 HB.

Why? I have no idea. I have no doubt the cylinder gap plays a role (Perhaps a large role), and I assume how smooth/tight/loose the barrel is could have an affect, but would be guessing at it.

 

[BiknSwans]

Your velocities sound about right based on my experiences. I've loaded a lot 124gr lead, FMJ and JHP bullets from various manufactures in the past year using BE-86. My current load for steel challenge is 4.7 gr under a 122gr Acme FP bullet. Here's the data from my Caldwell chrono from when I was working up that load;

Beretta 92FS-4.9" Barrel
4.4 1015 fps
4.6 1050 fps
4.8 1090 fps

Thanks eo1bart. My question now is, for the same or very similar bullet, if you reach or exceed the published maximum load velocity, even though you are well below the maximum load, should you stop? The average pressure has to be about the same in both cases, I would think. I'm not so sure about the maximum pressure.

 

[longdayjake]

I've settled on 5.9 grains of BE86. Velocities are amazing and the recoil is softer than I expected.

 

[rsrocket1]

My results are like longdayjakes. Faster than expected velocities and softer than expected recoil. I started loading BE-86 with 40 S&W (4.25" M&P40) and started with 5.6g with the Lee 401-175-TC powder coated (180g typical weight). Before using the chrony, I shot a couple boxes full and was amazed at the low recoil and improved accuracy (most of my accuracy consistencies are recoil dependent). So when I clocked the rounds, I was shocked that I was averaging 1004 fps. I thought I was below 900 fps. The odd thing was that an increase in charge resulted in lower than expected increases in velocity. 6.0g was averaging 1015 fps and 6.4g was averaging 1042 fps. These 20 bullets were the only ones I've shot at that high a charge. My standard charge will be 5.3g for a mid 900 fps load. At that speed, the recoil is very mild so the accuracy consistency for me is very good.

When shooting them in my Beretta, I was getting > 1200 fps with 5.6g using a powder coated Lee 356-120-TC @ 1.10". About 100 fps more than I usually shoot but the recoil felt no different. I'll be backing off of this load too.

 

[Rock185]

Hokie, barrel twist could certainly make a difference, but that is not the reason for the variations I mentioned. When fired in different guns, even if identical models/barrel lengths,etc., the finest factory ammo, or reloads by the most careful and precise reloader, fired on the same day, same temperature,same atmospheric pressure, same phase of the moon, etc. will give different velocities. This, because no two manufactured items are really exactly the same in dimension and finish. Within my humble experience, tighter chambers and bores will give higher velocities than chambers and/or bores few thousandths looser. As will a shorter or more abrupt leade into the rifling. In "identical" revolvers for instance, one will have a slightly wider barrel/cylinder gap than the other, a slightly tighter or looser chamber, slightly more or less headspace, a bore with a rougher or finer finish,etc. These minute differences all matter, no matter what powder is used. If you can find "Why Ballisticians Get Gray" by Dave Andrews, published in Speer manuals #9 and #12, Mr. Andrews explains it far better than I, and gives examples. I'm certainly not a ballistician, but have been a shooter and reloader, and chronographed enough factory and handloaded ammo in enough guns, to say my experience is consistent with what Mr. Andrews wrote back in 1974.......ymmv