SRH velocity questions. Slow gun, chrono,?????

OK, I don't live by the chrono, but this bothers me.
I come NOWHERE near the velocities listed in Hodgons handbook for their loads in my 7.5" SRH. I realize their 7.5"barrel may be a pressure barrel, but still... These records are from a few years ago, & all my readings are avgs from at least 6rds.
Here are a couple of loads I have the data handy for.
For 20.0 gr of H-110 with a 405 CP cast they show 1213fps. I was getting 988fps.
With 19.0 gr Lil'gun with the 405 CP they show 1219fps, & 21.0 1337fps. With 20.0 I recorded 1151. I was using 400gr cast from a Lee mold but as I recall velocity was about the same from Performance Cast bullets. (By the way, I have tried different primers in both loads & those were the fastest primers. WWLP).

Sooooo..... Those are some pretty HUGE differences, especially on the H-110.
Slow gun, whacky chrono, or lying book?
Never checked factory ammo. Only tried one chrono to try (old Shooting Chrony). It died & currently no chrono & no one to borrow from.
I know, work up an accurate load & go kill stuff.
Would still love some input.

I've always found their numbers a bit "optimistic" and have never been able to reach them with my loads.

That's been the opposite of what I've seen. Most of my handloads post velocities of 100 to 200 fps faster than what the manuals list. Did you apply a heavy crimp to the bullets? That can affect velocity, although usually not by that much.

Hodgdon's?

Hornady. Sorry, I thought you meant manuals in general.

There can be some significant differences among books, which is why it is a good idea to consult more than one. I don't use Hornady's manual but do use their bullets. What do they give for a 250 XTP with H110, heavy 45 Colt load?

I'll check when I get home.

.480 Ruger??

Yeah sorry Whit, 480 Ruger. I always forget there are other calibers!

They don't list a Ruger & T/C only load using that powder for the 250 grain bullet. However they do list data for H4227 with the 250 XTP using 20.5 grains at 1150 fps to 25.7 grains at 1400 fps out of a 10" T/C Contender.

one, the srh i've got 5 in our direct shooting and reloading circle and they run slower by about 100 fps vs the FA and they run about what the testing lab pressure barrels run. that said, play with the crimp a bit. i've found crimping a little in the first stage, then a second stand alone crimp that is a heavy heavy crimp allows the h110 to build up pressure and get much better velocity.

And Hodgdon shows 1150 fps with 20.0 from a 7" barrel. Surprisingly Hornady lists a higher max load, but if you extrapolate the data Hogdies would be about the same speed or a little faster, again from a 7" barrel.

to echo the information on the crimp, I recently tested this exact thing in a 45 Super revolver. Taper crimp v. combination taper and roll, and was seeing 75 fps difference with Longshot powder. When you consider I was only running 8 grains of powder, I though this to be pretty significant.

Craig