The Firing Line Forums

Go Back   The Firing Line Forums > The Skunkworks > Handloading, Reloading, and Bullet Casting

Reply
 
Thread Tools
Old July 22, 2012, 10:26 AM   #1
willyhunter1
Junior Member
 
Join Date: July 22, 2012
Location: georgia
Posts: 6
OAL .270 help

I am new to reloading ,but have loaded several rounds in 3 different calibers with no problems untill i got to the 270. I am using the lyman 49th edition and the lee loading manuals.
The book tells me a 150 gr. jacketed sp and gives me the hornady part number sp2740 with the min. oal of 3.285 inches, using IMR 4064. The problem is when i set the depth to this dimension i am nowhere near the canalure,and the cartridge will not chamber, so i smked the bullet and found that the seating depth on this riffle (a model 70 win) is 3.20 which gets me into the bullet canalure but puts me under my min.OAL any suggestions?

I am loading by the book
willyhunter1 is offline  
Old July 22, 2012, 10:31 AM   #2
mrawesome22
Senior Member
 
Join Date: November 9, 2005
Location: Ohio, Appalachia's foothills.
Posts: 3,779
Forget the book oal. If you are applying a crimp, load to the cannulure.

No crimp, seat the bullet ogive .030" from the rifling, find a good powder charge, then tweak the oal from there.

Sometimes oal will be determined by magazine length.

Sent from HenseMod6.
mrawesome22 is offline  
Old July 22, 2012, 11:21 AM   #3
willyhunter1
Junior Member
 
Join Date: July 22, 2012
Location: georgia
Posts: 6
Wont that run my pressure way up from seating to deep
willyhunter1 is offline  
Old July 22, 2012, 11:53 AM   #4
mrawesome22
Senior Member
 
Join Date: November 9, 2005
Location: Ohio, Appalachia's foothills.
Posts: 3,779
No. You should be starting at the start load and working your way up toward most accurate, or excessive pressure signs. Whichever comes first.

I would not get my hopes up with IMR4064. It's too fast to be ideal for the 270Win.

Sent from HenseMod6.
mrawesome22 is offline  
Old July 22, 2012, 12:32 PM   #5
willyhunter1
Junior Member
 
Join Date: July 22, 2012
Location: georgia
Posts: 6
Thanks im just concerned over the length being to short and i do start on the bottom end andwork up i just havent seen any of the loads they have listed beingthis far off espesially using the exact part numbers. The h4831 is probably the better choice but i had load data for the 4064 and was trying to use it up
willyhunter1 is offline  
Old July 22, 2012, 12:45 PM   #6
mrawesome22
Senior Member
 
Join Date: November 9, 2005
Location: Ohio, Appalachia's foothills.
Posts: 3,779
Did they seat to the cannulure?

If so, what is your case length compared to theirs?

Sent from HenseMod6.
mrawesome22 is offline  
Old July 22, 2012, 12:52 PM   #7
Unclenick
Staff
 
Join Date: March 4, 2005
Location: Ohio
Posts: 9,991
Willyhunter1,

Welcome to the forum.

It sounds like your minimum is a bad number. The SAAMI spec is COL from 3.065" to 3.340". Even then, SAAMI's numbers are concerned with magazine feed and compatibility as well as chambering, but with a standard nose profile. If you get a more blunt nose profile it may still jam the lands even within SAAMI maximum. There is nothing to prevent you from sizing down a .32 wadcutter and seating it flush with the case mouth, provided you develop your load with it seated that way. You just can't count on it to nose up a feed ramp properly and may have to chamber it singly.

Figure your bullet maker knew what he was doing with his own bullet's shape when he located the cannelure. Also be aware that typos creep into manuals sometimes and that when you aren't using the exact same gun the manual author used, that can mess it up too because your throat may be different.
__________________
Gunsite Orange Hat Family Member
CMP Certified GSM Master Instructor
NRA Certified Rifle Instructor
NRA Patron Member
Unclenick is offline  
Old July 22, 2012, 01:11 PM   #8
603Country
Senior Member
 
Join Date: January 6, 2011
Location: Thornton, Texas
Posts: 2,114
Willyhunter, you don't need a crimp on your 270 rounds, unless you just want to do it. I haven't crimped a rifle load in 35 years.

As for the powder, I use H4831sc and there are quite a few powders that will work better for you than IMR 4064 for velocity. That said, I did use 4064 in my Browning BAR 270 some years ago and it shot pretty darn good (3/4 inch at 100 yards) with the Nosler 130 gr Ballistic Tips. I shot many many deer with that load.
603Country is offline  
Old July 22, 2012, 01:41 PM   #9
willyhunter1
Junior Member
 
Join Date: July 22, 2012
Location: georgia
Posts: 6
I have tried with and without crimp i use a factory crimp just for the fact i use a pump action ona few of my other guns. The seating difference was.085 difference and didnt get me to the canalure. After i smoked it to find the lands i seated it 025 more andnow im in the canalure. As for the powder i dont target shoot much and all my rounds are for hunting white tails and hogs and my 30-06 shoots well with the imr4064. I appreciate all the posts
willyhunter1 is offline  
Old July 22, 2012, 10:25 PM   #10
farmerboy
Junior member
 
Join Date: May 16, 2009
Location: Central Texas
Posts: 1,343
Atleast try your calipers against a other set to check for accuracy and also agree that any literature can have typos so check 2-3 sources and also believe if you want a crimp set at cannalure set it but really you don't need a crimp if you don't want one.
farmerboy is offline  
Old July 23, 2012, 08:59 AM   #11
willyhunter1
Junior Member
 
Join Date: July 22, 2012
Location: georgia
Posts: 6
Yes sir ckecked my calipers and lymans and lee books both say the same as far as minimum length but that length wont chamber. It actually seated the bulletto the base of the canalure. I set it up like i should from that point i was just concerned at the depth of the bullet. I am seated in the canalure .025 off the lands total oal
3.215 vs the books 3.285
willyhunter1 is offline  
Old July 23, 2012, 09:20 AM   #12
steve4102
Senior Member
 
Join Date: December 23, 2005
Location: Minnesota
Posts: 1,974
Quote:
Wont that run my pressure way up from seating to deep
In straight walled pistol cartridges yes, in bottle necked rifle rounds like the 270, no. In fact seating deeper usually reduces pressure as the bullet get farther away from the rifling.

From Western Powders.

SPECIAL NOTE ON CARTRIDGE OVERALL LENGTH “COL”
It is important to note that the SAAMI “COL” values are for the firearms and ammunition manufacturers industry and must be seen as a
guideline only.
The individual reloader is free to adjust this dimension to suit their particular firearm-component-weapon combination.
This parameter is determined by various dimensions such as 1) magazine length (space), 2) freebore-lead dimensions of the barrel, 3)
ogive or profile of the projectile and 4) position of cannelure or crimp groove.
steve4102 is offline  
Old July 23, 2012, 09:34 AM   #13
Unclenick
Staff
 
Join Date: March 4, 2005
Location: Ohio
Posts: 9,991
You get chambers with quite a range of throat profiles, some with a long freebore before the bullet meets the lands and some not. You don't have the same gun Lyman used so their number need not necessarily match yours.

That said, I suspect the Lyman number is a misprint. I say that because I looked up the same bullet in Hornady's own manual it gives a COL of 3.210" in a case trimmed to 2.530"; 0.075" shorter than Lyman gives. Presumably Hornady knows where their own cannelure is, and I doubt Lyman ignored the cannelure (though they could have; you'd have to ask them).

Note that case length does affect COL when you crimp into a cannelure and that the cannelure covers a vertical span that gives you a short adjustment range. I usually seat so the case mouth is about 2/3 up a cannelure before crimping with a standard seating die's crimp shoulder. I have it 100% up for the Lee Factory Crimp. Some folks go half way up. There's some wiggle room here.

If you are 0.025" off the lands, you shouldn't get closer without backing loads off and working up to check for pressure signs, because pressure will be rising as you get closer and there is less gas bypass during bullet jump to the lands. It sounds like you have a chamber with a short freebore, more like a match chamber, but those can be good for accuracy, so I would just accommodate it and see how well the gun will shoot.
__________________
Gunsite Orange Hat Family Member
CMP Certified GSM Master Instructor
NRA Certified Rifle Instructor
NRA Patron Member
Unclenick is offline  
Old July 23, 2012, 11:48 AM   #14
wncchester
Senior Member
 
Join Date: December 1, 2002
Posts: 2,830
"... After i smoked it to find the lands i seated it 025 more andnow im in the canalure."

You're doing fine, shoot 'em. Within reason, seating deeper in rifles DECREASES peak pressure.
wncchester is offline  
Old July 23, 2012, 02:43 PM   #15
willyhunter1
Junior Member
 
Join Date: July 22, 2012
Location: georgia
Posts: 6
Thank you i was going to get ahornady book today. Im glad i found this site everyone has been helpful unlike other sites ive been to. I appreciate all the help and as i get into this new hobby of mine a little more, i know where i will seek advice.
willyhunter1 is offline  
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 05:49 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2013 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Contact Us
Page generated in 0.09091 seconds with 9 queries