First time with trapdoor

[hiram]

I have this trapdoor. 1873. I never shot it. It's about time.

I did my usual workup of BP 2f loads.

The results are in the pic. 18 shots, one keyhole -- don't know why.

Boolit is Lee 405 HB.

Sized to 457, pan lubed, basically emmert's. No grease cookie.

The load I will use works out to 57 on my powder thrower = 63.1 grains.

I tried an unsized cartridge with an unsized bullet and it chambered. My followup will be 5 shots unsized and lubed without a g cookie and 5 with a gc. I'll try the g cookie because the barrel is long.

[waksupi]

Did you slug the bore? I'm betting on undersized boolits. Some of those Trapdoors ran pretty big in the bore.

[Skipper]

+1

The 405 HB will probably drop at .459 unsized. Try them that way. You may need to go to .460 or larger.

[TXGunNut]

Distance?

[hiram]

100 yds. the other 17 had no signs of tilting.

They bullets drop at about 460 and they chamber. I will try then unsized.

The base is hollow, but if you put a grease cookie in, the base gets filled. Is this acceptable?

[waksupi]

Yep. Just fine to get some grease in your boolit hole!
Get the right size boolit, all of those holes should be in around an inch, and all flying point on.
If the .460 doesn't shoot better, try paper patching to get up to proper size.

[Nobade]

What are those boolits cast from? Unsized and the softer the better - pure lead if you have any works great and will fill the grooves.

Droptube in more powder, that helps too. My '73 likes the full 70gr. loads under that boolit. Unsized, dip lubed.

[HangFireW8]

Which shot keyholed? First? Last?

HF

[Skipper]

You didn't load up the rifling with powder fouling, did you? Do you wipe between shots?

[Bullshop]

I would join Nobade in questioning " what alloy".
With my TD rifles both slugg about .461" and I shoot the 405 Lee HB and heavier boolits cast of very soft alloy and have come to expect about 2 moa performance or very close to it out to 500 yards.
Even with my barrel groove of .461" diameter my rifles will still shoot the same with boolits as small as .458" diameter if the alloy is soft enough and the powder charge adiquate to obturate the boolit base to make a gass seal.
When I first started with the two rifles I now have after slugging the barrels I was very close to buying a custom mold that would drop at .463" but after learning a bit about the guns I found it absolutely not neccessarry. This is even true of an old Ideal mold I have for the # 457125 that will only drop a boolit a few .0000" (ten thousandths) over .457".

[Simonpie]

While others have success with the 405 boolits, I never have. I'd try some 500+ grain like 457125. I'm shooting a fairly worn and speckled bore.

[hiram]

The alloy is 100% lead. The keyhole was the 13th shot. I used a blowtube since wiping from the breech isn't convenient.

Today I shot 5 shots unsized (.460) and lubed without a g cookie and 5 with a gc.

The results were very good IMO. I shot high, but the no grease cookie group was 4 in 3" and my fault flier. The grease cookie loads were 3 in 4" and 2 far out shots.

I'm amazed at the age / accuracy of the firearm. The sights are a little difficult to use because they are so fine. I'm shooting high but have an idea how to handle that without altering the firearm.

[Bullshop]

Shooting high at 100 yards is normal with original sights, at least so with the Buffington sight.
The nearest setting with the Buffington is 150 yards. I am not at all familiar with the 1873 sight so dont know if it allows a closer setting.
My rifles shoot the 405gn Lee HB well out to 300 or 400 yards but for the longer ranges the 500+ gn boolits do much better.

[fouronesix]

You can lower the point of impact without altering the rifle. If you have a standard TD front sight- it is simple blade held in with a small pin. Drift the pin out and simply replace the blade with a slightly taller one. Easy to fashion one out of some mild sheet steel or brass. Keep the original blade in case you want to go back to original. If it is a Buffington sight, raise the staff and at the lowest setting, use the peep. My senior eyes aren't what they used to be and the peep with the front blade is about as good a sight picture as is possible without going to glass optics.
If it has the older "sky jump" ramp rear sight then you could look around for an alternative to use in its place. Tang mounted peeps on TDs are problematic

[Larry Gibson]

+ another for not sizing the 405HB. Shoot it as cast in the TD.

Larry Gibson

[John Boy]

Hiram, use 1:20 alloy instead of pure Pb and a 6 o'clock hold ... you will like the groups

[hiram]

I'll try 1:20 -- I have it for my RB.

I checked the front sight and it is pinned --- looks like an easy fix..

[Bullshop]

But if you change the front blade your sight settings will no longer be correct.
It is very enjoyable ( for me) to go for a walk about in the hills with TD and range finder in hand. Pick out a distant rock or something you can see well in the sights. Range it with the range finder and set the sight on the rifle for that range.
If you use a load that is reasonably close to the service round hits come quite easily at long range. The service round with the 500gn boolit was between 1270 and 1330 fps.
If you dont already have Spence and Pat Wolfs book on loading for the TD do yourself a favor and contact Pat and get a copy.

[waksupi]

I bet if you tried a 500 gr. boolit, the sight would be right.

[JeffinNZ]

Keyhole? I thought he musta put his thumb through the target.

I agree on the 20-1 alloy. Maybe even 30-1 if you are light on tin/solder.