sticky bolt sometimes

[luke]

I worked a load for a buddy's rifle with used remington brass. The load consists of 73grs of retumbo with a winchester magnum primer and 162gr A-Max bullet. About 1 in 5 rounds it is hard to open the bolt. The max that i have found for this load is 73.5. Other than the occasional sticky bolt there is no signs of pressure. I have been loading for about 5 years and never had this problem. Any info would be greatly appreciated.

 

[ScottB]

Bolt lift.....

#1: How sure that your powder measure is dropping 73grains? (Just asking, trying to check off things on the list)

#2: Brass from the same lot? (Inconsistant brass thickness can cause some pressure issues)

#3: Is the bolt hard to lift on round number one or round number five? Or just whenever? (Heating)




Scott

 

[7 loader]

Back off the load 1/2 a gr. And Scott is also right. The brass maybe from different lotts. Weigh the brass and sort them according to weight.gun)

 

[luke]

The brass is all remington head stamp but it is some that i just got here or there. Most was picked up at the range(once fired) that guys just left.I hand measure every charge of powder so that is consistent. One thing I did notice today was that some of the brass after being resized and case trimmed would fit tight in the chamber, even without primer ,powder or bullets. Could this be some or maybe all of the problem I am having. thanks again.

 

[baldhunter]

I ran into that once with some range brass that had been loaded to extreme high pressures.Some had expanded so much,that the primer pockets would not even hold a primer.Every once in awhile I 'd get one that would give me a sticky bolt lift.It wasn't that my load was too hot,it was the brass was bad.Got rid of that brass and my problems went away.

 

[J E Custom]

Back off the load 1/2 a gr. And Scott is also right. The brass maybe from different lotts. Weigh the brass and sort them according to weight.gun)

+1

Back off 1/2 to 1 grain or seat the bullet .005 to .010 deeper.(Shorter COL).

J E CUSTON

 

[luke]

Bald hunter thanks for the info. I am gonna try some new brass in the gun and see what happens. J E Costoms I will try backing off some if the new brass dont work as that seems to be the most offered remedy. The coal is set to saami so do you think it would be ok to go shorter? Although I have been reloading for a few years I am far from knowing the effects of changing stuff like that. I am one of the "the books say this" people and set my stuff up according to that.

 

[J E Custom]

Bald hunter thanks for the info. I am gonna try some new brass in the gun and see what happens. J E Costoms I will try backing off some if the new brass dont work as that seems to be the most offered remedy. The coal is set to saami so do you think it would be ok to go shorter? Although I have been reloading for a few years I am far from knowing the effects of changing stuff like that. I am one of the "the books say this" people and set my stuff up according to that.

Some chambers are shorter than SAAMI specs. Even though they are factory chambers they can have short necks or little or no free bore.

So the best thing to do is make sure this is not the case By loading a dummy round (NO powder
and/or no primer) long and trying it in your chamber real carefully by trying to close the bolt
very lightly and seating it deeper each time by.010 to .015 until the bolt will close.

The bullet will seat in the lands .005 to .010 thousandths so once you get the bolt to close with
no effort reduce the COL by .010 and that will give you max overall length.

Once you have done this if it is still longer than SAAMI length you can eliminate this concern

And to your question about the effects, the more free bore you have the less pressure you will
have (To a point). If you seat the bullet against the lands you will have to start with much lower
powder charges.

J E CUSTOM

 

[longarm05]

i have ran into this 2 times from 2 different customers .... was all the cases trimmed to proper length? just something to check. if some of the cases are to long it will cause the brass to "pinch" down on the bullet and cause high pressure "ie" hard bolt lift..................just somethink to try..good luck and good shooting james

 

[luke]

I loaded the same loads as i have been havin the problems with today.I loaded 20 rounds with resized brass that fit right (not to tight) and 5 rounds with the tight fitting brass. The tight fitting brass was the problem. Not one sticky bolt with the brass that we could easily close the bolt on but the brass that was tight to start with would almost not even open. Thanks to every one that helped out and gave me some more knowledge so i can remedy this problem should it ever happen again.

 

[eaglesnester]

i worked a load for a buddy's rifle with used remington brass. The load consists of 73grs of retumbo with a winchester magnum primer and 162gr a-max bullet. About 1 in 5 rounds it is hard to open the bolt. The max that i have found for this load is 73.5. Other than the occasional sticky bolt there is no signs of pressure. I have been loading for about 5 years and never had this problem. Any info would be greatly appreciated.

you are over the safe load limits. Cut back your load immediately. I dont care what your scales say or what your load is, you are over pressure. immediately cut back 1 grain. The sticky bolt itself is a sign of overpressure. You could have a hot batch of powder, or there could be other less obivious causes, however cut back the load and go from there.