Brewer, do you have a chronograph?
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Brewer, do you have a chronograph?
Don't but can borrow one. Mostly I try to use published data, stay in the range as long as there is no pressure signs, and match the load to what I want it to do. I will need to test 6.5 grendel rounds so I can dope for drop and wind at long range, so will have to chrono some stuff this summer.
I went ahead and plugged in the Lee 200, changed the weight to 210, put in 2.10" for COAL and 16" for barrel. I then set up for a ladder table output as shown below.
I only found a few posted 350L loads out on the web with 2400 and a 200+ bullet. Max charge I found was 17 gr, so be very careful working up loads using the data below. The bottom half of the table should be considered "suspect".
I know you have both a Bolt gun and an AR. Definitely work up in the bolt gun first, then if you want to try some in the AR, drop down from where you stopped in the bolt gun and work back up.
Code:Cartridge : .350 Legend
Bullet : .358, 200, LEE C358-200-RF
Useable Case Capaci: 25.604 grain H2O = 1.662 cm³
Cartridge O.A.L. L6: 2.100 inch = 53.34 mm
Barrel Length : 16.0 inch = 406.4 mm
Powder : Alliant 2400
Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms
-11.1 71 16.00 1647 1264 33972 3480 100.0 1.197
-10.0 72 16.20 1662 1288 35014 3506 100.0 1.182
-08.9 73 16.40 1677 1312 36080 3532 100.0 1.167
-07.8 74 16.60 1693 1336 37171 3556 100.0 1.152
-06.7 75 16.80 1708 1360 38287 3581 100.0 1.138
-05.6 76 17.00 1723 1384 39429 3606 100.0 1.124
-04.4 77 17.20 1737 1408 40597 3630 100.0 1.111
-03.3 78 17.40 1752 1432 41793 3654 100.0 1.097
-02.2 79 17.60 1767 1456 43016 3678 100.0 1.084
-01.1 79 17.80 1781 1480 44267 3703 100.0 1.072
+00.0 80 18.00 1796 1504 45547 3726 100.0 1.059
+01.1 81 18.20 1810 1528 46856 3750 100.0 1.047 ! Near Maximum !
+02.2 82 18.40 1824 1552 48196 3774 100.0 1.035 ! Near Maximum !
+03.3 83 18.60 1838 1576 49567 3797 100.0 1.024 ! Near Maximum !
+04.4 84 18.80 1852 1600 50969 3821 100.0 1.012 ! Near Maximum !
+05.6 85 19.00 1866 1624 52405 3844 100.0 1.001 ! Near Maximum !
Results caused by ± 10% powder lot-to-lot burning rate variation using nominal charge
Data for burning rate increased by 10% relative to nominal value:
+Ba 80 18.00 1836 1572 52928 3592 100.0 1.006 ! Near Maximum !
Data for burning rate decreased by 10% relative to nominal value:
-Ba 80 18.00 1733 1400 38143 3901 99.6 1.133
I tossed in the table and then and went back and edited some more text in and added in some lower charges. Go back and look at the text now at the top of the post.
Okay, it took me a while, but I knew that there was some better 2400 data out for the 350L. Tomme Boy posted a screenshot of 165 / 170 gr Hornady data for the 350 at post 582 of this thread. The screenshot is fuzzy, but it looks like they got:
With the above, I am less concerned about the previous Quickload (QL) data, but see that it can be improved as described below. As a warning, this data will approximate what Hornady got with their batch of powder. Your batch may burn faster. If you want to approach maximum loads, use of a chrono is strongly recommended. Do not exceed the predicted velocities for the maximum allowed pressure you are willing to run at.Code:Powder Charge Velocity
2400 21.7 2000
2400 22.2 2050
2400 22.9* 2100 (* could be 22.7)
My version of QL does not have these bullets, so I had to add a bullet with an estimated length (0.80”). I ran the Hornady data and found the default parameters gave me 100 fps more velocity and it gave higher pressures. I adjusted the burn rate (Ba) parameter to 1.002 and QL converged pretty good with the Hornady data.
I then re-ran the Lee 200 (adjusted to 210 grs) and Mal Paso's suggested COAL. Based on the 170 above, Hornady stopped at a point where QL pressure got to around 44,000 psi. I set up the ladder based on this being a max. Based on the below, stopping at between 1800 fps and 1850 fps should be giving approximately the same chamber pressure as the Hornady load for the 170 gr at 2100 fps. Based on the default 2400 burn rate used in my previous QL runs, you could get to this velocity range starting at just over 18 grs.Code:Cartridge : .350 Legend
Bullet : .356, 170, Hornady approximation
Cartridge O.A.L. L6: 2.245 inch = 57.02 mm
Barrel Length : 16.0 inch = 406.4 mm
Powder : Alliant 2400 (Ba adjusted to 1.002)
Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms
-04.5 82 21.40 1987 1490 37037 4678 98.2 1.020
-04.0 82 21.50 1995 1502 37501 4696 98.3 1.015
-03.6 83 21.60 2002 1514 37969 4714 98.4 1.009
-03.1 83 21.70 2010 1525 38442 4731 98.5 1.004
-02.7 83 21.80 2018 1537 38920 4749 98.6 0.998
-02.2 84 21.90 2026 1549 39403 4766 98.7 0.993
-01.8 84 22.00 2034 1561 39891 4783 98.7 0.988
-01.3 85 22.10 2041 1573 40384 4799 98.8 0.983
-00.9 85 22.20 2049 1585 40882 4816 98.9 0.978
-00.4 85 22.30 2057 1597 41386 4832 99.0 0.972
+00.0 86 22.40 2064 1609 41894 4847 99.1 0.967
+00.4 86 22.50 2072 1621 42408 4863 99.1 0.962
+00.9 87 22.60 2080 1633 42928 4878 99.2 0.957
+01.3 87 22.70 2087 1645 43452 4894 99.3 0.952
+01.8 87 22.80 2095 1657 43982 4909 99.3 0.948
+02.2 88 22.90 2103 1669 44518 4923 99.4 0.943
Code:Cartridge : .350 Legend
Bullet : .358, 200, LEE C358-200-RF, weight set at 210
Cartridge O.A.L. L6: 2.140 inch = 54.36 mm
Barrel Length : 16.0 inch = 406.4 mm
Powder : Alliant 2400 (Ba adjusted to 1.002)
Step Fill. Charge Vel. Energy Pmax Pmuz Prop.Burnt B_Time
% % Grains fps ft.lbs psi psi % ms
-10.5 73 17.00 1613 1214 29421 3778 97.5 1.262
-09.5 74 17.20 1629 1238 30292 3818 97.8 1.246
-08.4 75 17.40 1645 1262 31183 3858 98.0 1.230
-07.4 76 17.60 1661 1286 32095 3896 98.3 1.215
-06.3 77 17.80 1676 1310 33028 3933 98.5 1.200
-05.3 77 18.00 1692 1335 33982 3970 98.7 1.185
-04.2 78 18.20 1707 1359 34958 4005 98.9 1.170
-03.2 79 18.40 1723 1384 35956 4039 99.1 1.156
-02.1 80 18.60 1738 1408 36977 4072 99.2 1.142
-01.1 81 18.80 1753 1433 38022 4104 99.4 1.129
+00.0 82 19.00 1768 1458 39091 4135 99.5 1.116
+01.1 83 19.20 1783 1482 40185 4165 99.6 1.103
+02.1 83 19.40 1798 1507 41303 4193 99.7 1.090
+03.2 84 19.60 1813 1532 42447 4221 99.8 1.077
+04.2 85 19.80 1827 1557 43618 4247 99.9 1.065
+05.3 86 20.00 1842 1582 44816 4272 99.9 1.053
See https://castboolits.gunloads.com/sho...=1#post4816659 for seating/OAL of the Lee 200
Attention to the amount of the exposed shank is critical given the Legend's short freebore.
Excellent bullet by the way . . .
I am confident the powder charges so magnum primers may reduce the spread. The only published data with pressure is for the RCBS at 208g with 22-23g W296 for 47-55K and 1910-1990 FPS So I am very close.
The Boolit was the 38-200 RCBS (202g) Gas Checked and lubed over 21g of A11FS with a CCI Small Rifle Primer. The rifle was an AR15 16" barrel, carbine length gas system.
16 shots 1 error, not mine, public range, lol
Average 1912 FPS
Standard Deviation 27.5
Min 1835 FPS
Max 1945 FPS
Spread 110 FPS
I think that's it.
Nope COL 2.140"
Howzat?
The brass looked good, felt good in the sizer and I've got it tumbling now. Primers had rounded shoulders and firing pin dent.
Thanks for the effort. I will probably start at 17 grains and work my way up to 18 first. If there are no pressure signs, I will cautiously move higher.
I would not at all be surprised if the limit on the Hornady loads were simply the amount of powder you can fit in the case. I set up some test loads of IMR4227 with the 170 grain interlocks and it was very obvious that the max charge Hodgdon offers up is about the most of the powder you can fit in the case and still make COAL limits. From fooling with 2400 in 30-06 it seems like it is a pretty forgiving powder to experiment with.
Yes, I plan on running this in a bolt gun. For now the AR only sees jacketed just to keep things simple. If I find I load I like real well in the bolt I may give it a try in the AR, but I am going into this assuming this is a bolt only proposition.
I found a canister of 1680 and the only load data I found max is 24.0 grains under a 180 gr. jacketed bullet. So start load for 200 gr. cast should be around 19.0 grains?
Alliant data at https://shootersreference.com/reload...a/357-maximum/ shows up to 30 grs of 1680 for both a 180 and a 200 in the 357 Max with listed pressures under 40,000. There were other loads that had much lower max values. The reason for the range of max listed charges is bullet seating depth and resultant load density.
When I was working up loads with Wc680 (milsurp version of 1680), I found that just under 100% load density (~1/32" air gap) worked best in my 357AR Max (ballistic twin to the 350L). This was true for my custom powder coat NLG cast bullets in both 180 gr and 200 gr. Starting with a load that gives an air gap of 1/8" and working up is probably a better recommendation than choosing a starting charge weight without understanding the resultant fill percentage.
What a spread. Think I will start a bit higher up. 1/8th inch air space meaning from the mouth of the case? Is it clean burning when in the pressure range it likes? At any rate have to wait til Sunday to burn any powder.
I was talking about the air gap in the loaded round.
In other words, from the base of the seated bullet to the surface of the powder.
For the 350L, 1680 is typically considered a litter slower than optimum. This usually means that you can use "a case full" of powder. For some powders (typically extruded) this means some amount of compression. Some folks use 1680 (a ball powder) compressed, but I was not happy compressing my powder in my gun. So for 1680, I tend to recommend considering "a case full" with no compression (100% load density) as real close to the maximum.
For both the 357 Max and the 350L, seating depth can vary a lot depending on bullet and gun. Case capacities can also vary from brand to brand. If your target maximum is 100% load density, you have to factor in your COAL and your components.
I don't like to compress ball powders much either. Hitting the press shortly.
Doesn't look correct note pressure of HDY 180 gr SSPB compared to the other 180 gr bullets listed.
Attachment 298284