Hi all, need some advice on what to look for and what parts need to be replaced on a colt series 70 mark IV 45acp . history I bought new back in the 70's . had a short trigger put in and changed the sights have shot it maybe 5000 rounds all most all reloads of mine. I had not shot it much in last ten years. I want to use it for bullseye shooting.
I always hold hammer back when closing slide the way I was taught, went to do some practice and for got to hold hammer back gun went bang when slide closed (scary) was pointed down range I due have good safety habits.
so I did the safety checks, safety works, grip safety works, but when I close slide the hammer will fallow most of the time but all of the time
what parts due you think I need to replace and or repair
thanksjavascript:emoticon(':?:')
colt series 70 / hammer falls when slide closes
Moderators: Bullseye, Moderators
This could be one of several things. Your left and center leaf on the 1911 sear spring may not be providing enough tension to hold he sear in engagement with the hammer. You could have a weakened mainspring which can cause the sear to lose engagement during the slide closing. Or, the sear and hammer could be out of proper engagement. The angle between the hammer and sear may be negative, meaning that they tend to slip off of capture as the mating angle of the hammer is more than 90°.
R,
Bullseye
R,
Bullseye
You may just be able to rebend the center and left legs of your sear spring for a little more tension and the problem could be as simple as that to solve. What is the current weight of your trigger?
You can replace the mainspring without having to adjust anything but I would only do that if the sear spring did not solve the problem.
Buying a new hammer and sear will mean a trigger job is in order. These are not usually drop-in parts. And the ones that are do not give you optimum trigger pull or a clean break, something you'll appreciate if you're going to shoot bullseye.
R,
Bullseye
You can replace the mainspring without having to adjust anything but I would only do that if the sear spring did not solve the problem.
Buying a new hammer and sear will mean a trigger job is in order. These are not usually drop-in parts. And the ones that are do not give you optimum trigger pull or a clean break, something you'll appreciate if you're going to shoot bullseye.
R,
Bullseye
I bent the sear spring and it seems to work now. I think maybe I need to have a good gun smith look it over, when I took out the sear and hammer
and looked at it with magnification it had spur on sear secondary cut that look like it was not wearing all the way across I honed the spur off and tried again it did not change any thing then I measured sear spring off of a parallel
bar to see how bend was in the forks then bent them .10 more and tried again still the hammer follows slide but caught on half cock so I bent them
another .10 (.20 total) from where they were tried again and it looks like I might have fix it tried it ten times and work right every time will take it to range in a few days and try live ammo.
does any one know of a good smith in the Wichita Kansas area that work on bullseye guns? I think it needs a good check up.
thanks Bullseye
and looked at it with magnification it had spur on sear secondary cut that look like it was not wearing all the way across I honed the spur off and tried again it did not change any thing then I measured sear spring off of a parallel
bar to see how bend was in the forks then bent them .10 more and tried again still the hammer follows slide but caught on half cock so I bent them
another .10 (.20 total) from where they were tried again and it looks like I might have fix it tried it ten times and work right every time will take it to range in a few days and try live ammo.
does any one know of a good smith in the Wichita Kansas area that work on bullseye guns? I think it needs a good check up.
thanks Bullseye
Overall, you really shouldn't notice much of an increase on your trigger pull just that the sear and trigger have more positive pressure to reduce bounce. Now, be sure when you go out to the range that you only load no more than two rounds at a time in the magazine, until you're absolutely sure that the sear will stay engaged with the hammer hooks. You do not want to experience a fully auto sequence as it will blow through whatever is in the magazine faster than you can believe.
R,
Bullseye
R,
Bullseye
shot it to day loaded 1 round in mag and tried it five times, loaded 2 round in mag and tried it five times, loaded 3 round in mag tried it five times it work right every time. here is what I did load mag in gun griped with bought hands with trigger finger out side off guard not on trigger and released slide hammer did not fallow.
then I read another book and it said to hold trigger back and release slide I tried this and it worked ok but I did not try this with live ammo.
when you due this test which way is the right way?
and trigger pull weight I would say is double what it was but crisp no creep
I shot 50 round not as good a group as normal due to trigger pull but think I can get use to it, think I will try and make a gauge.
then I read another book and it said to hold trigger back and release slide I tried this and it worked ok but I did not try this with live ammo.
when you due this test which way is the right way?
and trigger pull weight I would say is double what it was but crisp no creep
I shot 50 round not as good a group as normal due to trigger pull but think I can get use to it, think I will try and make a gauge.
it is a series 70 mark IV government model I bought new in the mid 70 not sure what year and was shooting with a five man team PPC coarse and was having some trouble so one team member said you need a short trigger and I let him put a short trigger in I don't know if he did and thing else that he did not tell me about I don't think so then another team member gave me a adjustable rear sight and I bought a tall front sight and in stalled them my self
and bought dillon square deal and set it at 4gr bullseye with 185gr lswc have and used this for PPC coarse I have shot may be 5000 rounds through it.
now I want to use it for a starter gun for bullseye coarse.
and bought dillon square deal and set it at 4gr bullseye with 185gr lswc have and used this for PPC coarse I have shot may be 5000 rounds through it.
now I want to use it for a starter gun for bullseye coarse.
it will be out side 2700 match with 50 yard slow fire targets. I got interested when at my local in door range they were shooting a 22 bullseye league in winter I have done this two years and some of the guys invited me to shoot at there out door range in the summer wher they have 2700 match so I am trying to gear up for that but don't have a lot of money to spend, but have bought some good guns to do it with in past not knowing they would be bullseye guns lucky I guess S&W m41, S&W m14, Colt series 70.
I shoot for fun and personal challenge I shoot 730 to 789 in indoor with 22.
I shoot for fun and personal challenge I shoot 730 to 789 in indoor with 22.
I will see how good I can do, when shooting PPC we shot 15 rounds at 7 yards, 15 rounds at 15 yards, and 20 rounds at 25 yards in side two handed.
and at my average score was 492 out of 500.
but one hand at 50 yards will be different game I have been doing a lot of reading here and on bullseye-list and think I will start out with 200gr lswc for 50 yard line and see what happens.
might have to send it off and have it built in to real wad gun or maybe just by a new wad gun. which ever I will have to sell some other guns, have to many that I don't shoot anyway.
and at my average score was 492 out of 500.
but one hand at 50 yards will be different game I have been doing a lot of reading here and on bullseye-list and think I will start out with 200gr lswc for 50 yard line and see what happens.
might have to send it off and have it built in to real wad gun or maybe just by a new wad gun. which ever I will have to sell some other guns, have to many that I don't shoot anyway.
I've shot PPC with a stock Colt and that was no problem based on the target scoring ring size. However shooting out to 50 yards with one is a different story the scoring rings on a bullseye target are far smaller. The (B-6) 50 yard slow fire target's scoring rings are the same size as a 25 yard (B-8) target, the (B-6) slow fire target just has the 8 ring blackened to make the aiming black appear the same size as it would at 25 yards. I don't know what kind of group your pistol can hold with a stock barrel and bushing. Keep that in mind if you're not grouping well. You may be outshooting your equipment.
R,
Bullseye
R,
Bullseye