Cartridge oal question

ke32 · September 12, 2015, 09:17 AM

Hello I'm new to reloading and I'm reloading 130 grain Berger bullet classic hunter for the 270 wsm. i loaded it to the Berger manual coal of 2.86 but when i load it the load is too long. it jams in the lands.

I'm looking for help and advice on how to proceed. I'd like to know if it's safe to shorten the cartridge oal?

Any help provided would be greatly appreciated.

jwrowland77 · September 12, 2015, 09:21 AM

Save yourself the aggravation, and buy a Hornady OAL Gauge and the Hornady Bullet Comparator set. The comparator measures to the ogive, which is where you want to measure too.

What you ran into is why we always start low and work our way up.

**Unclenick** · September 12, 2015, 10:01 AM

Ke32,

Welcome to the forum.

The 2.860" COL is merely the SAAMI maximum that you cannot exceed without risking the cartridge might not fit into some rifle's magazine. The SAAMI drawing shows a range of 2.560" to 2.860" for normal bullet shapes. So the SAAMI standard maximum may not be the correct COL is correct for your bullet. Berger should list a COL for the individual bullet that is different from their other bullets. If they don't (I don't have their data) then call them to ask for one.

Below is an exaggerated illustration showing two different bullet profiles seated to the same distance off the lands of the rifling (the jamming clearance, so to speak). But because of the profile differences, the COL's have to be very different to have the same throat clearance. This is the issue you are running into.

To get a ballpark figure, pick up a 3/16" brass rod at Lowe's or if your cleaning rod is a Dewey with a male thread you can use it. Remove the bolt from your rifle and stick one of your long cartridges into the chamber and press the bullet up against the land by pressing with your finger on the head of the cartridge. Hold it there while you run the rod in from the muzzle until it contacts the bullet tip. Use a pencil to mark the rod where it is flush with the muzzle.

Push the cartridge out with the rod. Put the bolt back in and close it. Run the rod in until it stops on the face of the bolt. Mark it with a pencil where it is flush with the muzzle.

Remove the rod and measure the distance between the two marks. This is the COL at which your bullet jams the lands. Since this won't be a super precise measurement and since bullet lengths vary some, I would subtract 0.030" from the result and call that your new starting COL and work a load up with that if Berger doesn't tell you anything different.

In making this measurement, the more flat and square the end of the rod is, the more accurate it will be. Just be sure the ejector on the bolt doesn't fool you about where the bolt face is located. If you want to buy a tool and get more precise measurements, that's fine, but this should get you in the ballpark.

T. O'Heir · September 12, 2015, 01:27 PM

Reduce the OAL to 2.730". That's the OAL given for a .270 WSM 130 by Hodgdon. Check the case lengths too.
Then, if you want to play with the 'off the lands' game, load a bullet loose but at the 2.860", chamber the cartridge. That should push the bullet into the case and give you the chamber length of your rifle. Then back off the length by about 20 thou(there is no formula for find the OAL your rifle likes best. it's entirely trial and error.).

ke32 · September 12, 2015, 11:05 PM

I followed your advice with the rod and worked it back to .02 off the lands. Going shooting tomorrow, hopefully I get good results.

Thank you for the responses, I really appreciate it!

September 12, 2015, 09:17 AM	#1
ke32 Junior Member Join Date: September 11, 2015 Posts: 2	Cartridge oal question Hello I'm new to reloading and I'm reloading 130 grain Berger bullet classic hunter for the 270 wsm. i loaded it to the Berger manual coal of 2.86 but when i load it the load is too long. it jams in the lands. I'm looking for help and advice on how to proceed. I'd like to know if it's safe to shorten the cartridge oal? Any help provided would be greatly appreciated.

September 12, 2015, 10:01 AM	#3
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,063	Ke32, Welcome to the forum. The 2.860" COL is merely the SAAMI maximum that you cannot exceed without risking the cartridge might not fit into some rifle's magazine. The SAAMI drawing shows a range of 2.560" to 2.860" for normal bullet shapes. So the SAAMI standard maximum may not be the correct COL is correct for your bullet. Berger should list a COL for the individual bullet that is different from their other bullets. If they don't (I don't have their data) then call them to ask for one. Below is an exaggerated illustration showing two different bullet profiles seated to the same distance off the lands of the rifling (the jamming clearance, so to speak). But because of the profile differences, the COL's have to be very different to have the same throat clearance. This is the issue you are running into. To get a ballpark figure, pick up a 3/16" brass rod at Lowe's or if your cleaning rod is a Dewey with a male thread you can use it. Remove the bolt from your rifle and stick one of your long cartridges into the chamber and press the bullet up against the land by pressing with your finger on the head of the cartridge. Hold it there while you run the rod in from the muzzle until it contacts the bullet tip. Use a pencil to mark the rod where it is flush with the muzzle. Push the cartridge out with the rod. Put the bolt back in and close it. Run the rod in until it stops on the face of the bolt. Mark it with a pencil where it is flush with the muzzle. Remove the rod and measure the distance between the two marks. This is the COL at which your bullet jams the lands. Since this won't be a super precise measurement and since bullet lengths vary some, I would subtract 0.030" from the result and call that your new starting COL and work a load up with that if Berger doesn't tell you anything different. In making this measurement, the more flat and square the end of the rod is, the more accurate it will be. Just be sure the ejector on the bolt doesn't fool you about where the bolt face is located. If you want to buy a tool and get more precise measurements, that's fine, but this should get you in the ballpark. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

September 12, 2015, 01:27 PM	#4
T. O'Heir Senior Member Join Date: February 13, 2002 Location: Canada Posts: 12,453	Reduce the OAL to 2.730". That's the OAL given for a .270 WSM 130 by Hodgdon. Check the case lengths too. Then, if you want to play with the 'off the lands' game, load a bullet loose but at the 2.860", chamber the cartridge. That should push the bullet into the case and give you the chamber length of your rifle. Then back off the length by about 20 thou(there is no formula for find the OAL your rifle likes best. it's entirely trial and error.). __________________ Spelling and grammar count!

September 12, 2015, 09:21 AM	#2
jwrowland77 Senior Member Join Date: March 23, 2012 Location: Conway, Arkansas Posts: 1,398	Save yourself the aggravation, and buy a Hornady OAL Gauge and the Hornady Bullet Comparator set. The comparator measures to the ogive, which is where you want to measure too. What you ran into is why we always start low and work our way up.

September 12, 2015, 11:05 PM	#5
ke32 Junior Member Join Date: September 11, 2015 Posts: 2	I followed your advice with the rod and worked it back to .02 off the lands. Going shooting tomorrow, hopefully I get good results. Thank you for the responses, I really appreciate it!