Is it safe to seat a bullet where it touches the rifling?

[DalesCarpentry]

I have found a good load for my 22-250 and not I would like to play around with the seating depth a little to see if my groups tighten up any more. Is it safe to seat a bullet where it touches the rifling? I am just concerned that seating a bullet where the rifling starts may increase pressure. I thought I would start there and shorten it a a little until I get back to the recomended COL. Thanks and take care Dale

[R.W.Dale]

I have found a good load for my 22-250 and not I would like to play around with the seating depth a little to see if my groups tighten up any more. Is it safe to seat a bullet where it touches the rifling? I am just concerned that seating a bullet where the rifling starts may increase pressure. I thought I would start there and shorten it a a little until I get back to the recomended COL. Thanks and take care Dale

it depends. I did it for my bench gun, but on commercial rifles you usually have mag or COL constraints that make doing so much less practicle.

As long as you start low and work up it shouldn't cause any safety issues with the exception of solid copper bullets.

[DalesCarpentry]

I have found a good load for my 22-250 and not I would like to play around with the seating depth a little to see if my groups tighten up any more. Is it safe to seat a bullet where it touches the rifling? I am just concerned that seating a bullet where the rifling starts may increase pressure. I thought I would start there and shorten it a a little until I get back to the recomended COL. Thanks and take care Dale

it depends. I did it for my bench gun, but on commercial rifles you usually have mag or COL constraints that make doing so much less practicle.

As long as you start low and work up it shouldn't cause any safety issues with the exception of solid copper bullets.

I have a Remington 700 SPS Varmint that is a BDL style and I have loaded a few just where the rifling starts and it still works in the mag so I guess all is good. Thanks Dale

[securitysix]

I am just concerned that seating a bullet where the rifling starts may increase pressure.

As well you should be, because it's not "may", but "will" increase pressure.  If you are well under max load, you can get away with it, but if you're near or at the max load, which I think you are (we're talking about the 40.5 grain charge of H380, right?), it would be best to work back up to that load if you are going to have the bullet seated into the rifling.  

Load up a couple of rounds at each charge weight you originally used in developing the load but with the OAL set to put the bullet just into the rifling.  Shoot the lower ones first and work your way up through them.  If you see any sign of pressure, stop shooting.  If you get back to the load you're using without pressure signs, then you're probably OK.

[Dee]

A 22-250 in that regards is much like a 25-06. You seat a bullet touching the rifling, and you could get gas or much worse right back in your face. If you load the 22-250 to factory specs most will shoot far closer than the shooter is capable of shooting.

[DalesCarpentry]

I am just concerned that seating a bullet where the rifling starts may increase pressure.

As well you should be, because it's not "may", but "will" increase pressure.  If you are well under max load, you can get away with it, but if you're near or at the max load, which I think you are (we're talking about the 40.5 grain charge of H380, right?), it would be best to work back up to that load if you are going to have the bullet seated into the rifling.  

Load up a couple of rounds at each charge weight you originally used in developing the load but with the OAL set to put the bullet just into the rifling.  Shoot the lower ones first and work your way up through them.  If you see any sign of pressure, stop shooting.  If you get back to the load you're using without pressure signs, then you're probably OK.

I will not shoot those loads then. I will stop at 0.010" from the rifling. Thanks Dale

[Autorim]

Dale, how are you measuring the dimension to the rifling leade?

[DalesCarpentry]

Dale, how are you measuring the dimension to the rifling leade?

This is the method I used. Thanks Dale
http://www.gboreloaded.com/forums//index.php/topic,112672.msg1098350243.html

[wncchester]

"I will not shoot those loads then. I will stop at 0.010" from the rifling. Thanks Dale"

1.   Few factory sporters shoot their best touching the lands and the potential problems make it undesirable.  Bench shooters often use softly held bullets that need contact with the lands to force start pressures high enough to achieve a good powder burn.  We sport shooters rarely, if ever, need that.

2.   Not sure what you mean with "stop at 0.010 from" the lands.  That's a fairly good place to start and then move deeper in steps of 5 0r 10 thou until you find the best OAL range for good accuracy.  That's likely to be 20 thou to as much as 60 thou, or more, off the lands.

3.   There is no "recommended" OAL.   Book OAL is only a suggested starting point, same as the powder charges.    What you see in the books is what the book makers used for their rifle and bullets to compile the load data, it may not have been a good seating point for accuracy at all.

[Win 1917]

it would be best to work back up to that load if you are going to have the bullet seated into the rifling. 

+1
 

[TXSPIKE]

I don't load my bullets into the lands,but this is how I find how far out I can go to find them and then I seat in from that measurement.I take an empty case that was fired in the rifle I'm checking.I then dent the neck a little,just enough to hold the bullet so there is just a little resistance when you slide a bullet into the neck.Place the bullet that you are going to reload into the neck,seating it in say,1/4 inch.I then slowly chamber the round in my rifle and close bolt complete,slowly open back up the bolt and remove the cartridge and carefully measure.Do this a couple of times,making sure you pull the bullet back out a little,then chamber,remove and measure.you should get the same measurement each time.So what you've done here is,you've found your COL to the lands with that type of bullet.Every bullet type has a little different olgive,so you have to do this for every different bullet type you use.I keep records of this and seat my bullets in a little from my max COL,that way I know for sure I'm not jammed into the lands,which could cause a pressure spike.

[DalesCarpentry]

I don't load my bullets into the lands,but this is how I find how far out I can go to find them and then I seat in from that measurement.I take an empty case that was fired in the rifle I'm checking.I then dent the neck a little,just enough to hold the bullet so there is just a little resistance when you slide a bullet into the neck.Place the bullet that you are going to reload into the neck,seating it in say,1/4 inch.I then slowly chamber the round in my rifle and close bolt complete,slowly open back up the bolt and remove the cartridge and carefully measure.Do this a couple of times,making sure you pull the bullet back out a little,then chamber,remove and measure.you should get the same measurement each time.So what you've done here is,you've found your COL to the lands with that type of bullet.Every bullet type has a little different olgive,so you have to do this for every different bullet type you use.I keep records of this and seat my bullets in a little from my max COL,that way I know for sure I'm not jammed into the lands,which could cause a pressure spike.

Thanks for the information. That is very simular to the way I have done it and seems to work great. Take care Dale

[myarmor]

In my 308 XR-100 I load them toching the lands, but they are Matchkings and are longer than most bullets, plus my chamber is tight and has a long throat as well. Play with it a little and see what your rifle likes. They have covered the precautions well 




-Aaron

[R.W.Dale]

I don't load my bullets into the lands,but this is how I find how far out I can go to find them and then I seat in from that measurement.I take an empty case that was fired in the rifle I'm checking.I then dent the neck a little,just enough to hold the bullet so there is just a little resistance when you slide a bullet into the neck.Place the bullet that you are going to reload into the neck,seating it in say,1/4 inch.I then slowly chamber the round in my rifle and close bolt complete,slowly open back up the bolt and remove the cartridge and carefully measure.Do this a couple of times,making sure you pull the bullet back out a little,then chamber,remove and measure.you should get the same measurement each time.So what you've done here is,you've found your COL to the lands with that type of bullet.Every bullet type has a little different olgive,so you have to do this for every different bullet type you use.I keep records of this and seat my bullets in a little from my max COL,that way I know for sure I'm not jammed into the lands,which could cause a pressure spike.

Actually if you have the right equipment you don't have to

Theres a comparator tool that allows you to compare and measure a bullets shank to the point where it is full bore sized to the case head. This allows you to only make the measurement you outline once and carry that data over to any other bullet. I use the method you outline in conjunction with my PTG bullet comparator, once arriving at a figure I record that measurement on my die box and can seat any bullet .xx" off the lands simply by comparing seating depth w the comparator to this figure.

http://www.midwayusa.com/viewProduct/?productNumber=746974

this tool is by far the best sub $20 I've spent on equipment to date

[Win 1917]

Thanks for posting that krochus. What a brilliant idea that tool is!! I've tried to copy some complicated comparators I've seen with the limited tools I have in the garage but with very limited success. For $20 that would accomplish exactly what I need.

[R.W.Dale]

Glad to help