I have a few suggestions. I would not be too quick to blame the SB brass, as you could easily have a headspace problem. Start with mild loads with your hew brass. You will then have fireformed cases matching your unique chamber. These cases should be neck sized only from then on. If, after working up to full power loads, you still have case problems, then you will likely benefit from a larger bolt head. Enfields are wonderful, historic, rifles, and great for reloading, but there is often enough chamber variation to require special reloading techniques for best results. You are gonna have fun with this rifle....DanM

Ummm...I have no idea how the smiley faces got there in place of the number eight. lets see if it happens again:

Here is my loaddata for 800X. All charges were hand weighed and fired through my 6" Glock model 40.

10MM175SWCPC
800X8.5gr WLP

String 3
     1)   1260.0     33.8
     2)   1191.0    -35.2
     3)   1242.0     15.8
     4)   1238.0     11.8
     5)   1184.0    -42.2
     6)   1242.0     15.8

       High:   1260.0
        Low:   1184.0
       E.S.:     76.0
       Ave.:   1226.2
       S.D.:     28.3

10MM175SWCPC
800X9.0WLP

String 4
     1)   1330.0     53.1
     2)   1252.0    -24.9
     3)   1237.0    -39.9
     4)   1241.0    -35.9
     5)   1243.0    -33.9
     6)   1317.0     40.1
     7)   1215.0    -61.9
        1264.0    -12.9
     9)   1342.0     65.1
    10)   1345.0     68.1
    11)   1260.0    -16.9

       High:   1345.0
        Low:   1215.0
       E.S.:    130.0
       Ave.:   1276.9
       S.D.:     45.0

10mm175LeeSWCPC
800X 9.5gr

String 5
     1)   1386.0      6.1
     2)   1342.0    -37.9
     3)   1445.0     65.1 f
     4)   1403.0     23.1
     5)   1365.0    -14.9
     6)   1364.0    -15.9
     7)   1385.0      5.1
        1350.0    -29.9
     9)   1379.0     -0.9

       High:   1445.0
        Low:   1342.0
       E.S.:    103.0
       Ave.:   1379.9
       S.D.:     29.1

The pills were cast from the Lee 175SWC 6cav mold which works well, but has a 3-4 grain weight variation between cavities. Bullets were then powder coated and sized to .401". I need to run a similar test with bullets from my NOE mold which had almost no weight variation between the 4 cavities.

Yep....We do have a popular dirt bike race track here. Also a 1/8 mile drag strip. I can just hear them from my yard on some Saturday nights. Good American fun!

I should mention that my home cast bullets are powder coated, eliminating any problem of lead accumulation in the bore. 

I live in East Bend, NC. A fine place to be!

The bullet is my 162gr cast HP from an MP mold. They shoot very well with every load I have tried. But I dont remember what load I was using for this demo. Right now that is my only mold for 10mm. It is a top quality brass mold. My next mold will be a 180WFN. Good quality molds like these are expensive. Or maybe my next purchase should be a good red dot to fit the MOS system. Either would be useful.

Here is a link to a little video of me having some fun with my Glock M40: https://www.youtube.com/watch?v=bNbEjGWKYR8
I really enjoy that pistol and the caliber! Wish I had a better video editing program.....

My next little project will be to make up some ballistic gelatin and see if the 162HPs actually hold together at these velocities. They blow up water jugs in a big way, but I have never tried to recover any fired bullets.

Here are results I have been getting with my Glock Model 40, with the long slide and 6" barrel. This pistol has a 20lb recoil spring installed, and I am thinking about upping that to a 22lb unit. I have only been shooting my home cast powder coated bullets. The 162HPs are from a Mihec mold, and the 175s are from a Lee mold. My chrono is a CEDM2. Obviously this data is presented for reference only, and used with great caution in other firearms.

10MM162HPPC
AA9 13.4 WLP

     1)   1261.0    -37.2
     2)   1276.0    -22.2
     3)   1294.0     -4.2
     4)   1281.0    -17.2
     5)   1315.0     16.8
     6)   1259.0    -39.2
     7)   1303.0      4.8
        1347.0     48.8
     9)   1347.0     48.8
    10)   1266.0    -32.2
    11)   1239.0    -59.2
    12)   1263.0    -35.2
    13)   1333.0     34.8
    14)   1340.0     41.8
    15)   1337.0     38.8
    16)   1310.0     11.8

       High:   1347.0
        Low:   1239.0
       E.S.:    108.0
       Ave.:   1298.2
       S.D.:     34.6

10MM 162LHPPC
AA9: 15.0GR, F150
GLOCK40-6"

     1)   1364.0    -39.9
     2)   1395.0     -8.9
     3)   1415.0     11.1
     4)   1400.0     -3.9
     5)   1413.0      9.1
     6)   1406.0      2.1
     7)   1386.0    -17.9
        1403.0     -0.9
     9)   1425.0     21.1
    10)   1432.0     28.1

       High:   1432.0
        Low:   1364.0
       E.S.:     68.0
       Ave.:   1403.9
       S.D.:     18.6
This load is very accurate, but may be a bit over the top.

10MM162HPPC
APP9.0GR WLP (Alliant Power Pistol)
     1)   1358.0     10.9
     2)   1362.0     14.9
     3)   1289.0    -58.1
     4)   1382.0     34.9
     5)   1318.0    -29.1
     6)   1352.0      4.9
     7)   1365.0     17.9
        1373.0     25.9
     9)   1324.0    -23.1
    10)   1325.0    -22.1
    11)   1364.0     16.9
    12)   1379.0     31.9
    13)   1344.0     -3.1
    14)   1325.0    -22.1

       High:   1382.0
        Low:   1289.0
       E.S.:     93.0
       Ave.:   1347.1
       S.D.:     26.2


10MM162HPPC
  H800X 9.0 WLP           
     1)   1310.0     12.2
     2)   1315.0     17.2
     3)   1300.0      2.2
     4)   1283.0    -14.8
     5)   1288.0     -9.8
     6)   1277.0    -20.8
     7)   1286.0    -11.8
        1310.0     12.2
     9)   1299.0      1.2
    10)   1293.0     -4.8
    11)   1322.0     24.2
    12)   1290.0     -7.8

       High:   1322.0
        Low:   1277.0
       E.S.:     45.0
       Ave.:   1297.8
       S.D.:     13.4

Glock M40-10mm 6"
162 LHPPC MP Mold
Hogdon Longshot 10.1gr..

     1)   1437.0    -31.3
     2)   1476.0      7.7
     3)   1474.0      5.7
     4)   1476.0      7.7
     5)   1458.0    -10.3
     6)   1462.0     -6.3
     7)   1460.0     -8.3
        1437.0    -31.3
     9)   1488.0     19.7
    10)   1482.0     13.7
    11)   1454.0    -14.3
    12)   1428.0    -40.3
    13)   1519.0     50.7 f
    14)   1496.0     27.7
    15)   1469.0      0.7
    16)   1476.0      7.7

       High:   1519.0
        Low:   1428.0
       E.S.:     91.0
       Ave.:   1468.3
       S.D.:     22.5

10MMLee175SWCPC
AA9:13.5GR

String 8
     1)   1252.0     19.1
     2)   1263.0     30.1
     3)   1227.0     -5.9
     4)   1252.0     19.1
     5)   1221.0    -11.9
     6)   1229.0     -3.9
     7)   1185.0    -47.9
        1212.0    -20.9
     9)   1229.0     -3.9
    10)   1259.0     26.1

       High:   1263.0
        Low:   1185.0
       E.S.:     78.0
       Ave.:   1232.9
       S.D.:     22.9

10MM175SWCPC
800X8.5gr WLP

String 3
     1)   1260.0     33.8
     2)   1191.0    -35.2
     3)   1242.0     15.8
     4)   1238.0     11.8
     5)   1184.0    -42.2
     6)   1242.0     15.8

       High:   1260.0
        Low:   1184.0
       E.S.:     76.0
       Ave.:   1226.2
       S.D.:     28.3

10MM175SWCPC
800X9.0WLP

String 4
     1)   1330.0     53.1
     2)   1252.0    -24.9
     3)   1237.0    -39.9
     4)   1241.0    -35.9
     5)   1243.0    -33.9
     6)   1317.0     40.1
     7)   1215.0    -61.9
        1264.0    -12.9
     9)   1342.0     65.1
    10)   1345.0     68.1
    11)   1260.0    -16.9

       High:   1345.0
        Low:   1215.0
       E.S.:    130.0
       Ave.:   1276.9
       S.D.:     45.0

10mm175LeeSWCPC
800X 9.5gr

String 5
     1)   1386.0      6.1
     2)   1342.0    -37.9
     3)   1445.0     65.1 f
     4)   1403.0     23.1
     5)   1365.0    -14.9
     6)   1364.0    -15.9
     7)   1385.0      5.1
        1350.0    -29.9
     9)   1379.0     -0.9

       High:   1445.0
        Low:   1342.0
       E.S.:    103.0
       Ave.:   1379.9
       S.D.:     29.1

10mm 175LeeTLSWCPC
AA9 13.2gr WLP
good accuracy


String 1
     1)   1130.0    -27.4
     2)   1156.0     -1.4
     3)   1191.0     33.6
     4)   1188.0     30.6
     5)   1135.0    -22.4
     6)   1164.0      6.6
     7)   1161.0      3.6
        1164.0      6.6
     9)   1128.0    -29.4

       High:   1191.0
        Low:   1128.0
       E.S.:     63.0
       Ave.:   1157.4
       S.D.:     21.8


1OMM175SWCPC
AA9 13.8GR WLP

String 2
     1)   1212.0     19.7
     2)   1176.0    -16.3
     3)   1221.0     28.7
     4)   1220.0     27.7
     5)   1202.0      9.7
     6)   1210.0     17.7
     7)   1206.0     13.7
        1177.0    -15.3
     9)   1203.0     10.7
    10)   1211.0     18.7
    11)   1191.0     -1.3
    12)   1079.0   -113.3 f

       High:   1221.0
        Low:   1079.0
       E.S.:    142.0
       Ave.:   1192.3
       S.D.:     36.9

10mm Glock40-6"
Alliant Blue Dot 9.5g4r.
Lee 175 SWCPC .401"

String 3
     1)   1142.0    -36.6
     2)   1218.0     39.4
     3)   1213.0     34.4
     4)   1146.0    -32.6
     5)   1222.0     43.4
     6)   1209.0     30.4
     7)   1119.0               -59.6
        1039.0   -139.6 f
     9)   1212.0     33.4
    10)   1180.0      1.4
    11)   1208.0     29.4
    12)   1201.0     22.4
    13)   1166.0    -12.6
    14)   1195.0     16.4
    15)   1209.0     30.4

       High:   1222.0
        Low:   1039.0
       E.S.:    183.0
       Ave.:   1178.6
       S.D.:     48.2

10MM 175SWCPC
ABD 9.8GR WLP  (Alliant Blue Dot)

String 2
     1)   1283.0     31.7
     2)   1260.0      8.7
     3)   1236.0    -15.3
     4)   1245.0     -6.3
     5)   1179.0    -72.3
     6)   1194.0    -57.3
     7)   1273.0     21.7
        1260.0      8.7
     9)   1263.0     11.7
    10)   1258.0      6.7
    11)   1316.0     64.7
    12)   1249.0     -2.3

       High:   1316.0
        Low:   1179.0
       E.S.:    137.0
       Ave.:   1251.3
       S.D.:     35.1

10mmSWCPC  (Alliant Power Pistol)
APP ; 9.0gr, Lee175SWCPC

String 6
     1)   1324.0    -11.2
     2)   1317.0    -18.2
     3)   1324.0    -11.2
     4)   1328.0     -7.2
     5)   1346.0     10.8
     6)   1355.0     19.8
     7)   1356.0     20.8
        1326.0     -9.2
     9)   1341.0      5.8

       High:   1356.0
        Low:   1317.0
       E.S.:     39.0
       Ave.:   1335.2
       S.D.:     13.7

10MMLee175SWCPC
HLS:9.1gr (Hogdon Long Shot)

String 7
     1)   1305.0     -2.1
     2)   1298.0     -9.1
     3)   1319.0     11.9
     4)   1318.0     10.9
     5)   1315.0      7.9
     6)   1294.0    -13.1
     7)   1319.0     11.9
        1300.0     -7.1
     9)   1298.0     -9.1
    10)   1305.0     -2.1

       High:   1319.0
        Low:   1294.0
       E.S.:     25.0
       Ave.:   1307.1
       S.D.:      9.3

I had only a little Hogdon Long Shot left in the can to play with. I need to get some more for further testing. Looks like I will have to special order it, as it is proving hard to find. It may turn out to be a favorite. As of now, AA9 is my first choice. Ummm, there are a bunch of smiley faces showing up in the preview.  They seem to be replacing the numeral 8.  I have no idea how they got there. If they show in the post, please ignore....Sorry

I pay little or no attention to listed OAL when loading a new bullet design. My method  is to load five or six to determine max magazine length. Making sure that the new bullets feed smoothly out of the mag without any nose drag against the front of the mag. To accomplish this I make a few that are too long and gradually reduce their OAL until they flick smoothly out of the mag with no hang ups due to nose drag. Then I do a plunk test making sure that the new carts seat fully at that max mag length. If the new carts pass the plunk test then I have my ideal OAL. I have always followed the 'longer is better' dictum for best feeding in self loaders. Also, all my feed ramps are polished to a bright mirror finish with Craytex bobs and Dremel. I am another LFCD devotee, using one on all auto loads.


edit....OOPS, I see that you have achieved success, and my comments were unneeded. Good on you!