Is This Muzzle Crown In Bad Shape?

[GMW]

74663My Springfield Trapdoor will put 5 rounds in a 2.5" group at 65yds. My load is 66grs of 2F Goex Express with a Fed 215 primer and a .060 fiber card. My bullet is the 1881 from a Saeco mould. Will a new muzzle crown help my groups tighten up or is this muzzle not that bad? I want to use my ole girl in a military rifle shoot that will be competing against AR15's, M1A1's, 1903's and other rifles. They all must shoot cast bullets and that is why I think I could have a fighting chance.
74662

[country gent]

Examine it with a good magnifying glass and look for dings dents and rub marks. When shooting the lubed cast boolits is there a grease star at the muzzle? Is it even all the way around or noticibly heavier in one spot/area? Pick up a brass ( not plated) round headed screw with a head 3/4" in dia ( around 3/8") lightly swirl rotate this on the muzzle Bright spots indicate high points. Some light lapping compound and rotate back and forth 4-5 times rotate 1/4 turn rotate back and forth 4-5 times rotate 1/3 turn repeat this thry several complete rotations. A patch put between the head and barrel with some flitz or shimichrome and repeat the rotation process again brings up a nice polished even crown. Its hard to tell from a picture on as fine detail of the crown. Look and see what you have the lube star tells alot. On my match rifles I would touch up the crown every 1000 rds or so just for peace of mind.

[country gent]

Also label and save the screw as it can be reused over and over and ounce the 2 are mated the screw cuts much faster.

[fouronesix]

Can't tell 100% from the photo but the bruise on the crown radius doesn't look like it reached the crown edge itself. One easy, no harm thing to try is to find a round steel or brass ball of about 1" diameter along with some lapping compound and turn the ball by hand. Just find a ball that will mark the actual crown rim around the muzzle. Too large and it won't touch the area you want. Too small and it will go too deep and put the wrong kind of edge on the crown. Even a round head brass screw chucked in a drill along with some lapping compound will do the same thing as the ball. In both cases, keep even, light pressure in line with the bore. Turn for about 30 seconds, wipe the crown off and check in good light with a magnifying glass. You should see a thin bright ring right at the crown edge. IF that bright ring is even all the way around the edge, then that's about all you can or really should do without a full blown re-crown in a lathe. Those two simple methods are very low risk, are easy and won't change the specs of the original gun. And they might help accuracy a little and may reveal any hard-to-see damage to the crown.

[Matt85]

hard to be sure but it doesnt look too bad. a cleaner burning powder might shrink your groups though, something like KIK or Swiss would help. the new Goex powder has had some pretty good reviews to. my current load of 70 grains KIK 2F, 0.030 fiber wad, federal 215 primer, and a buffalo arms 460500 bullet lubed with SPG will regularly shoot a 2" group at 100 yards out of my old trapdoor (this load is still a work in progress).

-matt

[Don McDowell]

Jump the powder charge right on up to 70 grs, scrap the magnum primer in favor of a standard large rifle primer, groups are likely to tighten up.

[johnson1942]

years ago i bought a recrowning kit from brownells and have used it many many times since. the crown is very important and just one of the spokes in the wheel of accracy. too bad you dont live near me i would recrown it for nothing and it would be done in a 1/2 hour. remember to wipe the grease off of the crown after every shot, because the grease build up give the crown a diff. shape and can change your groups. all my crowns shine like chrome and are perfect.

[Matt85]

Jump the powder charge right on up to 70 grs, scrap the magnum primer in favor of a standard large rifle primer, groups are likely to tighten up.

people on this forum keep saying that but all the books ive ever read and my own personal experience disagree. I did a test by loading 50 identical cartridges with the only difference being the type/brand of primer (both standard and magnum). long story short, the federal magnum primers yielded the best groups by a long shot. now this was with one kind of powder (KIK 2F) so maybe a different brand of powder might ignite differently. but the increased accuracy was substantial, with standard primers the average group was 5-6" while the average group with magnum primers was 3-4" with federal magnum primers beating all with an average group of 2" (this test was performed at 100 yards from a bench). the load for my test was a basic 500 gr gov round nose bullet cast from 20-1 and lubed with SPG over 70 grains of KIK 2F with no wad in a Remington case using large rifle and large rifle magnum primers. the gun used in my test was an 1888 springfield trapdoor rifle dated 1891 with an outstanding bore.

-matt

[Cosmiceyes]

Do what countrygent said. You can use valve grinding compound if it's bad,"but"you have to work your way back to a fine 600 grit. I go to 1000 grit mirror fine.

[Don McDowell]

people on this forum keep saying that but all the books ive ever read and my own personal experience disagree. I did a test by loading 50 identical cartridges with the only difference being the type/brand of primer (both standard and magnum). long story short, the federal magnum primers yielded the best groups by a long shot. now this was with one kind of powder (KIK 2F) so maybe a different brand of powder might ignite differently. but the increased accuracy was substantial, with standard primers the average group was 5-6" while the average group with magnum primers was 3-4" with federal magnum primers beating all with an average group of 2" (this test was performed at 100 yards from a bench). the load for my test was a basic 500 gr gov round nose bullet cast from 20-1 and lubed with SPG over 70 grains of KIK 2F with no wad in a Remington case using large rifle and large rifle magnum primers. the gun used in my test was an 1888 springfield trapdoor rifle dated 1891 with an outstanding bore.

-matt

Your pretty lucky to get that result. When I switched from the cci primers to the federal magnum match primer, the KIK fouling got harder to deal with and accuracy left, and we got some leading due to the harder fouling. With Goex express groups just flat opened up to the point of being almost useless.
So your comment about " people on this forum keep saying that but" comes from experience.

[Matt85]

Your pretty lucky to get that result. When I switched from the cci primers to the federal magnum match primer, the KIK fouling got harder to deal with and accuracy left, and we got some leading due to the harder fouling. With Goex express groups just flat opened up to the point of being almost useless.
So your comment about " people on this forum keep saying that but" comes from experience.

that's a primer I have not tried yet. the primer that gave me the best accuracy were standard Federal 215's in the large blue box. the match primers probably burn different then the non-match primers. I can confirm that magnum primers produce harder fouling then non-magnum primers, but the harder fouling is a small price to pay for the improvement in accuracy I gained.

-matt

[hickstick_10]

In agreement with Don to increase your powder charge. Also move your target out to a full 100 yards for testing.

What diameter bullet is your mold dropping and what type of lube are you using?

[Boz330]

people on this forum keep saying that but all the books ive ever read and my own personal experience disagree. I did a test by loading 50 identical cartridges with the only difference being the type/brand of primer (both standard and magnum).

-matt

If it works for you by all means use them. Many of the books that recommend the magnum primers were written 20+ years ago when Goex was your only choice. Since then powder choices have improved dramatically as well as the number of people shooting BP and experimenting with it. Some of the old cranks recommended drilling out the primer holes as well, now we add primer wads to dull the flash.
I had no luck with magnum primers. One of my rifles loves Lg pistol primers and 2 others CCI BR-2s. Experimenting leads to what works in any given rifle. Primer wads have enhanced accuracy in every rifle that I have. What ever works.

Bob