Looking to shoot 178grain A-max out of a rem 700 5r and was wondering what OAL I should use or how to make it specific to the gun. Book states 2.8inch if I am not mistaken.
How to find the best OAL for your gun
- Thread starter Buckeye Scott
- Start date
Re: How to find the best OAL for your gun
Trial and error...
Some guns like it on the lands, others .020" off, other .040" off, some .100" off.. Do your load homework, hit the range and see what flies best..
Trial and error...
Some guns like it on the lands, others .020" off, other .040" off, some .100" off.. Do your load homework, hit the range and see what flies best..
Re: How to find the best OAL for your gun
only .308 I shoot at 2.8 OAL is for AR10 because of magazine dimensions. all my bolt guns are loaded longer, dont get hung up on the 2.8 dimension. load a dummy round long, mark the ogive thoroughly with some Dykem or black magic marker and try to chamber it. Keep seating the bullet further back into the case until it chambers without having to really push hard to close the bolt. When the bolt closes, look at your ogive for 5 square looking marks (rifling marks). Keep seating deeper and deeper in small increments (recoating the ogive every time with marker) until your 5 marks disappear and record this lenth as your distance to lands. With Amaxes, I start loading at the lands and work towards a jump of .015. You may be succesful with a much larger jump but i think youre gonna need the room in the case for more powder!
only .308 I shoot at 2.8 OAL is for AR10 because of magazine dimensions. all my bolt guns are loaded longer, dont get hung up on the 2.8 dimension. load a dummy round long, mark the ogive thoroughly with some Dykem or black magic marker and try to chamber it. Keep seating the bullet further back into the case until it chambers without having to really push hard to close the bolt. When the bolt closes, look at your ogive for 5 square looking marks (rifling marks). Keep seating deeper and deeper in small increments (recoating the ogive every time with marker) until your 5 marks disappear and record this lenth as your distance to lands. With Amaxes, I start loading at the lands and work towards a jump of .015. You may be succesful with a much larger jump but i think youre gonna need the room in the case for more powder!
Re: How to find the best OAL for your gun
Iv'e been shooting 168 SMK's and was told that they are very forgiving and many times work well with a jump of .1 which seems huge. I'm running them at .03 with good results. I was recently told that you can use 168 Amax's out to 1200 yards so I am switching to give it a try. It will be interesting to see where they like it.
Iv'e been shooting 168 SMK's and was told that they are very forgiving and many times work well with a jump of .1 which seems huge. I'm running them at .03 with good results. I was recently told that you can use 168 Amax's out to 1200 yards so I am switching to give it a try. It will be interesting to see where they like it.
Re: How to find the best OAL for your gun
The Amax is not as "jump forgiving" as the168 SMK, that's for sure
The Amax is not as "jump forgiving" as the168 SMK, that's for sure
Re: How to find the best OAL for your gun
Take a sized case and put 1 or 2 slits in the neckdown to the shoulder. Clean up the burrs. Place a bullet in the case and leave it long. Place it in the chamber and either close the bolt on it or push it with a dowell until the case shoulder makes contact with the chamber. Remove and measure. I have found with some chambers the case and bullet will have to be pushed back with a cleaning rod or dowell. Repeat several times and take note of measurments. This will give you a way to measure seating depth for each newbullet you try.
Take a sized case and put 1 or 2 slits in the neckdown to the shoulder. Clean up the burrs. Place a bullet in the case and leave it long. Place it in the chamber and either close the bolt on it or push it with a dowell until the case shoulder makes contact with the chamber. Remove and measure. I have found with some chambers the case and bullet will have to be pushed back with a cleaning rod or dowell. Repeat several times and take note of measurments. This will give you a way to measure seating depth for each newbullet you try.
Re: How to find the best OAL for your gun
For magazine fed rifles I usually go to the longest thing that will reliably cycle. The Bolt rifles are a different matter. I have some loaded the same length as factory loads. But most of it is loaded extra long to be hand fed only. However, as I rebarrel the factory rifles, I tell the tool grinder what bullet I'm shooting and how far off the lands I want it. You may have to send him a couple of rounds so he can get the measurments right. But that can make a world of difference. The 300 winmag and one of the 308s I had built would shoot just fine fed from the magazine. It measured just like I wanted it to.
If your gunsmith won't do that for you, maybe you need to ask someone else. If it's a REAL custom riflesmith he'll have several reamers of different specs in each caliber. If not just call Pacific and order your own reamer.
Good luck.
For magazine fed rifles I usually go to the longest thing that will reliably cycle. The Bolt rifles are a different matter. I have some loaded the same length as factory loads. But most of it is loaded extra long to be hand fed only. However, as I rebarrel the factory rifles, I tell the tool grinder what bullet I'm shooting and how far off the lands I want it. You may have to send him a couple of rounds so he can get the measurments right. But that can make a world of difference. The 300 winmag and one of the 308s I had built would shoot just fine fed from the magazine. It measured just like I wanted it to.
If your gunsmith won't do that for you, maybe you need to ask someone else. If it's a REAL custom riflesmith he'll have several reamers of different specs in each caliber. If not just call Pacific and order your own reamer.
Good luck.
Re: How to find the best OAL for your gun
Hornady sells a OAL guage for about 35 bucks. Get the 308 case for it and take some readings. Get the ogive dies to take the measurements to the ogive. As long as all the casses are trimmed the same length, your loads will all be equal.
Hornady sells a OAL guage for about 35 bucks. Get the 308 case for it and take some readings. Get the ogive dies to take the measurements to the ogive. As long as all the casses are trimmed the same length, your loads will all be equal.
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