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mac1911
06-17-2017, 08:59 AM
So I rotate through my rifles for the cmp matches and also over the past few years have been switching to cast loads for just about everything I shoot at CMP Games matches.
They are all shot at 200 yards or less so no need for long range.

Next up is a crusty nothing matching RC K98. When I first purchased this rifle hitting the back stop was about as good as it got. I then started loading for it and then was giving a 8mm lee mold 324-175. I was using trailboss for starters as I like the light loads it produces and its fun at 50 yards shooting cans and such. It was showing some promise until the powder shortage hit.
The mold drops to a touch over .325" and the sizer I got with the mold is a .325" and pretty much just seats the gas check.

so im going to start with 2400 and H4895 as that's what I have on hand.

its not the best looking bore but once I cleaned it up and played with the action screw tightness shes improved greatly. Las time out at a cmp match I shot the Yugo M75 sniper ammo. shot a 399/500 that was before I got my shooting Rx and before the powder shortage. should be fun


https://www.youtube.com/watch?v=an-9QBnqHHc

mac1911
06-18-2017, 01:56 PM
I have not had a lot of time to or for load development so im going to try three loads and if they are capable of holding the black of a SR1 target at 100 yards that's what I will go with.
So im going with these loads to start. All are going to use the Lee 324/175 gas checked and lubed with 2500, PPU cases and Wolf LR primers. 2.830" COL per data, . Im just going with the lyman Data for the H4895 starting load of 35 grains. I don't think my alloy will hold up to well to much more than 1800fps Im using clip on wheel weights with 2% tin added by means of som 70/30 solder.

the allot seems to work well in my other 30 cal family rifles.

Load one
35 grains H4895 Lyman data says 1670FPS

Load two
37 grains of H4895 I think this should get me aroun 1800fps just want to see how it does. I don't have time to set up the crony for testing.

load three
16 grains of 2400 its been a very good load in everything else so its worth a try.

Some day 5744r 4759 might be on the shelf locally to try but have not seen it yet.

http://i.imgur.com/JkVYZRy.jpg

Larry Gibson
06-18-2017, 04:17 PM
I suggest backing off on the H4895 starting at 26 gr and work up to 32 gr. Use a 3/4 - 1 gr Dacron filler. The velocities will start in the low 1700s, maybe high 16s) and will exceed the RPM Threshold at 1940 fps with the top end load. Here is a test I did with my 24/47 8x57 using a 190 gr bullet from GB mould. The test was to see what the accuracy difference was between my brass home made GCs and Hornady GCs and to see if accuracy was acceptable using the 450+ Berdan primed Turk cases I had. The bullets were only sorted to remove any visual defects. The M24/47 has a 6X scope on it. The 31 gr load was previously worked up using Hornady GCs.

Note the velocity of the 190 gr cast was mid 1800 fps with 31 gr 4895. With a 175 gr cast it should be into the 1900s if not higher.

197872

Larry Gibson

mac1911
06-19-2017, 07:07 PM
Interesting. I'm not one to shy away from using less powder.
I might just have to find time to crony these as the lyman starting load of 35 grains of H4895 is only 1640fps..
So far all I have loaded is the 35grain loads... I'm going to try and get out tomorrow of or Thursday. Maybe I will just do a crony test tomorrow and then test fire Thursday.

mac1911
06-22-2017, 05:06 PM
I suggest backing off on the H4895 starting at 26 gr and work up to 32 gr. Use a 3/4 - 1 gr Dacron filler. The velocities will start in the low 1700s, maybe high 16s) and will exceed the RPM Threshold at 1940 fps with the top end load. Here is a test I did with my 24/47 8x57 using a 190 gr bullet from GB mould. The test was to see what the accuracy difference was between my brass home made GCs and Hornady GCs and to see if accuracy was acceptable using the 450+ Berdan primed Turk cases I had. The bullets were only sorted to remove any visual defects. The M24/47 has a 6X scope on it. The 31 gr load was previously worked up using Hornady GCs.

Note the velocity of the 190 gr cast was mid 1800 fps with 31 gr 4895. With a 175 gr cast it should be into the 1900s if not higher.

197872

Larry Gibson
Larry i tried some 28 grain loads along with the 35s i had already loaded. Honestly the 35s shot ok but a bit stout for what I like to look forward to loading light cast loads. The 2400 rounds where nice little push just the way i like it.

i will try some H4895 from 28.5-32 grains to see if there is a node in that range I like.
sight setting was on 400 meters for all shots. I shot the 28 and 35 grain loads round robin alternating from top to bottom target. I did not have a third target on hand to shoot the 2400 in rotation
https://www.youtube.com/watch?v=0B7F58i9gVc&t=3s

mac1911
07-06-2017, 09:23 PM
Little trouble today.
I wanted to center up my windage a bit.
That went ok. Moved out to 200 yards.
Windage was ok but elevation is not working out to well.
With 16 grains of 2400 behind a 176-177 grain bullet holding at 6 o'clock I get nice centered hits at 100 yards with 500m setting. Move out to 200 yards 600m hits 8 ring low with a few splashes into the 9.
700m I'm more into the 7 ring high..should be fun trying to hold over or under.

Gewehr-Guy
07-07-2017, 08:01 AM
To get my groups centered I use little strips of paper as shims under the rear sight . When i find the right combination of paper shims , I measure with calipers and make one of brass or aluminum that wont blow away in the wind. If you change loads make several of different thicknesses.

mac1911
07-07-2017, 08:17 AM
To get my groups centered I use little strips of paper as shims under the rear sight . When i find the right combination of paper shims , I measure with calipers and make one of brass or aluminum that wont blow away in the wind. If you change loads make several of different thicknesses.

Not a bad idea. Although that would not be "legal" in cmp vintage match.
Im just surprised at how much the impact moves between 600-700 setting.
Moves a lot more than my 1903a3 with a simular load.

Gewehr-Guy
07-07-2017, 01:39 PM
Sorry, Range Officer, but I don't know how a .014in. thick blade of grass got stuck under my sight ladder ! [smilie=1:

mac1911
07-08-2017, 09:46 PM
Sorry, Range Officer, but I don't know how a .014in. thick blade of grass got stuck under my sight ladder ! [smilie=1:
well I will find out tomorrow...I noticed my sight will lock into the notches in between each setting...so I might find a nice happy medium with the "650" setting.

heres my 100 yard windage test...
http://i.imgur.com/Ds9izSx.jpg

before the inpacte where hitting in the 9/8 ring to the right. I made a "calculated guess on my sight tool adjustment and the low left shot was the result(400m)....so then I wanted to see where my "calculated guess" of 700m would impact that was the shot high left 5 ring. 3 rd shot on 500m was high left 9 ring.
seeing my windage was a little left for all 3 shots I cranked the sight another half turn with the sight tool and put the last 5 shots where there are in the 10 and X plenty good for me , this rifle and the load. So out to 200 500 hit just low of the black, 600 was in the black but low favoring the lower side of the 9 ring 700 put them high into th 9 and eight ring:evil::veryconfu
the happy thing is windage was good and if I can post the same groups tomorrow I should do well. its all up to off hand really....if I can post 90s in all three positions I will be in the hunt for the little trinkets

mac1911
07-10-2017, 09:29 PM
Well the match was a bust for me.
Shot ok in the prone slow fire match.
Still shooting a bit to the left but the big problem is I do not have a happy medium on the rear sight elevation at 200 yards.
It was either shoot low in the black and splash a few 8s and 10s or bring it up and shoot more 8s than in the black. Holding over was not very effective and I lost some points doing so.
Rapids where shot with out a hitch. Action is actually smooth and trigger although a bit rough was manageable.
I ended up shooting a 0 in rapids. At some point I knocked the rear sight down to 100m...happy to report pit crew reported and nice minute of woodchuck hole in the berm...ugh.
Off hand was about as good as I can muster. Although the pit crew said I did not shoot off all 10 shots. By this time I was already getting my gear together and just said enough is enough. My "score" with the 2 "missed" shots was 67 which is,about my average with off hand for 8 shots. Next time

dogmower
07-11-2017, 11:49 AM
8mm mauser? think imr 4198

nicholst55
07-11-2017, 05:47 PM
Brownells at least used to carry a taller front sight for Mausers. That might provide an answer for your elevation problems. Assuming that it would be legal, of course.

hc18flyer
07-11-2017, 10:58 PM
I recently ordered one for my M24/47 from Brownell's. hc18flyer

mac1911
07-14-2017, 10:24 PM
Brownells at least used to carry a taller front sight for Mausers. That might provide an answer for your elevation problems. Assuming that it would be legal, of course.

They do make a tall front sight but that makes your impact lower. I need shorter front sight. I do have a few sights I could modify. Like I did with the 1903a3.
I won't modify a sight until I find a decent load and I would like to get down to 3moa or less before I play with the front sight.

mac1911
07-14-2017, 10:25 PM
8mm mauser? think imr 4198

If I ever see a # of it locally I will give it a try... been looking for a few other cast friendly powders also.

Gewehr-Guy
07-15-2017, 06:51 AM
Also try RL-7, one of my favorite cast rifle powders for .30 cal. and 8mm.

Ray1946
08-03-2017, 11:18 PM
Amen to RL7! I have used it in 8mm and 7.5 Swiss. In both cartridges I used a tuft of dacron under the boolit and got very consistent velocities. It also meters extremely well.....................