Juggenrault89:
It sounds like a difference in reading and getting what you read.
We are all different, some learn better by seeing. I like to read, futz with it, then re-read as things become obviously I need to clarify.
Checking with your friend is a good idea. You will get some idea as you go along if he is a careful reloader or not. If not then find another source or more research. I know the Big Stores have reloading classes. I leaned at my step dads side and he was the best of neat, tidy and careful.
Cramp is learning curve and it sounds like you have it right. Eject a round form time to time and see if there is any setback.
Ok, this has to be taken carefully. This is getting into experienced reloader area for judgment. Always cross check any internet info both from posters and your manuals. If there is a significant disagreement on loads, stop.
Sierra is on the far edge of Unique, I would not use their high unless I crept up on it carefully. Newer manuals tend to be conservative so I am leary of that load. There can be mistakes and mis prints. I have 5 reloading manuals. Horandy and Sierra are the best two for wide variety of powder choices and they have wide range of bullets so you can find one close enough to work (as you go along)
Lymans manual is a good reference, they also list pressures and they do lead bullets as they supply casting molds for.
Lymans does not show 125 gr lead (round nose in this case) they do show 120 gr at 4.0 to 5.0. You can see how little there is there. 5 Grains bullet weight is close enough if you start low (no more than 4.2).
Sometimes the lowest loads won't cycle the action, ergo loading just a few at starting.
You might get a load at max won't cycle the action. At that point quit, get another powder and start over at the lowest load. If there is a repeat then something is wrong.
The Semi tip (truncated,) they do not list Unique for (also 120 gr.). That means it was not accurate, not that it won't work.
The issue with the Glock is leading as you noted. Hard cast can be shot in that gun but you have to be very careful and check it.
Check your bullet supplier and do some research on that specific casting.
Some are very good about quality control and others not so much.
If you do decide to shoot after research:
Best would be 5 rounds at the end of a shooting session, strip the gun down when you get home and carefully check for lead.
If none, then 10 at the end of a session, check gun, repeat, add 5 more. Once you reach a maximum you might shoot, then each time take the gun down and clean and check for lead.
Its the drawback of Polygonal rifling. It can be done but like a lot its tread very carefully area.
9mm: Max pressure is 34,000 psi. the max loads on the Lymans are 33,000 psi. As powder is non linear, you can easily have a jump with a tenth or two over what the gun will take. A different primer than what was used for the load can push it over.
Glock may put a bulge in the brass. If its bad enough you can't re-size it.
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