The Firing Line Forums

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

Reply
 
Thread Tools
Old May 10, 2012, 08:54 AM   #1
Jevyod
Senior Member
 
Join Date: May 5, 2012
Location: Pennsylvania
Posts: 105
Factory ammo too long?

So here's the deal; am working on starting my 1st reloads ( 7mm rem mag ) and i ran into something I thought seemed odd. I was making a dummy round to see where to seat my bullets. I was using the method of using a marker to scribble out rifling and seat a bit deeper till I had just a hint and then backed off another half turn. I ended up with an oal of 3.143. That seemed to my inexperience like a big difference from the manual's 3.290. So that got me thinking about the factory ammo I had been shooting. I remembered that sometimes i had to force the bolt closed. So i got one of those and tried it out and sure enough, i had some serious rifling marks. So would that create a higher pressure? I always thought it had a pretty serrious recoil. I also found one that I had fired, and there was a slight flattening of the primer. So now I have several questions; does my gun just not like factory ammo? Is it abnormal to need to shorten the length so much? Is my gun just "weird"? And i really do not like the way it looks with the bullets seated so far in the casing. Can I trim the casing shorter than the "trim to" length? I am open for education on this issue cause am still learning lots!
Ps. Am shooting a Remington 700
Jevyod is offline  
Old May 10, 2012, 09:27 AM   #2
wncchester
Senior Member
 
Join Date: December 1, 2002
Posts: 2,832
Jev, we can understand your question but OAL is much simplier than you have been led to believe.

First, no weapon cares where the bullet nose hangs in space, all that matters is the jump before the bullet hits the rifling. Seating long in rifles can jam the lands and that does increase start pressure without any real increase in speed so we need to avoid that. Seating short insures a bit of bullet free run before hitting the rifling and that reduces peak pressure and, usually, speed - but not much. It's rare for factory ammo to contact the lands in a factory chamber and that's not what most of us would want but it's likely safe to use.

Next, load book OAL is simply what the book team used to develop the listed data, it's not a 'rule' for the rest of us any more than their powder charges are. It matters not what someone else does, IF we're going to custom make our ammo to work best in our rigs we need to experiment with both charges and seating to find what works best for us.

Back when I started reloading very little loading data included even a suggestion for OAL, we just set it as we wanted according to our bullet, chamber and magazine and then developed our charge. We lived.
wncchester is offline  
Old May 10, 2012, 09:33 AM   #3
Sport45
Senior Member
 
Join Date: May 25, 1999
Location: Too close to Houston
Posts: 4,076
I'd have a 'smith check it for headspace and see if it doesn't need finish reaming. A factory round shouldn't jam into the rifling. Trimming the brass won't help that.
__________________
Proud member of the NRA and Texas State Rifle Association. Registered and active voter.
Sport45 is offline  
Old May 10, 2012, 10:29 AM   #4
10 Spot Terminator
Senior Member
 
Join Date: January 3, 2008
Location: Central Oregon
Posts: 348
Hi Jev,

Different bullets have different shapes to them with the point where the diameter of the bullet equals the bore diameter in your weapon being called the ogive. This will dictate the maximum seating depth allowed on any particular rifle cartridge. There are tools available from Hornady to measure this very thing and and the differences between similar bullets of the same weight by different manufacturers can be quite different. Seating shorter is not abnormal based on bullet selection and longer can get to be an issue if the length exceeds the magazine length or if there is an insufficient amount of the bullet base left seated in the catrige case neck . Many match shooters have their sweetheart loads set so long as to only allow hand feeding them one at a time . Being able to measure this prior to building your loads can come in very handy when picking a bullet that best compliments the amount of setback needed to fit the magazine, be seated well enough into the case and get the bullet jump to the lands ( rifling ) into a workable range as the freebore and or some throat errosion on well used firearms will be different. Hope this helps and if you need more insight here feel free to PM me.

10 Spot
10 Spot Terminator is offline  
Old May 11, 2012, 06:12 AM   #5
Jevyod
Senior Member
 
Join Date: May 5, 2012
Location: Pennsylvania
Posts: 105
Thanks for the info guys! That helps clear some things up. So much to learn yet.
Jevyod is offline  
Old May 11, 2012, 07:43 AM   #6
243winxb
Senior Member
 
Join Date: July 26, 2011
Posts: 1,051
7mm Rem Mag

A factory round shouldn't jam into the rifling. http://www.saami.org/PubResources/CC...n%20Magnum.pdf Contact Remington- http://www.remington.com/pages/our-c...pany-info.aspx

Last edited by 243winxb; May 11, 2012 at 08:09 AM.
243winxb is offline  
Old May 11, 2012, 07:47 AM   #7
flyguy958
Senior Member
 
Join Date: June 27, 2009
Location: SC
Posts: 160
OAL is not the best way to measure seating depth. I found this out using Nosler Partition 180 grain bullets. I failed to notice they have two different designs for the same bullet. OAL of these are totally different. Below are links to the two. See the difference in OAL of the bullet. I now test each new bullet seating depth in the rifle before I start loading.


http://www.midwayusa.com/product/627...tzer-box-of-50


http://www.midwayusa.com/product/212...oint-box-of-50
flyguy958 is offline  
Old May 13, 2012, 01:14 PM   #8
Lost Sheep
Senior Member
 
Join Date: January 24, 2009
Location: Anchorage Alaska
Posts: 3,043
Are you sure about that?

Quote:
Originally Posted by wncchester
First, no weapon cares where the bullet nose hangs in space,
I have always understood that, whether there is a length of empty chamber in front of the bullet, "freebore" in the barrel, the bullet just contacts (kisses) the rifling or jams hard against it can make a great deal of difference, and usually does.

Sorry to disagree with you, but I must differ.

Lost Sheep
Lost Sheep is offline  
Old May 18, 2012, 08:06 AM   #9
Jevyod
Senior Member
 
Join Date: May 5, 2012
Location: Pennsylvania
Posts: 105
Just an update; I went ahead and took it to a gunsmith last eve and he couldn't find anything the matter. He seemed to think it was simply a tight chamber and recommended sending it back to Remington. So it should be going out today. While I was there, he chambered one of my factory rounds and soon found out what I meant when I said it jammed! It jammed so badly, that he had to tap on the bolt to get it out. And come out it did, just the casing and powder all over the place. The bullet stayed in the barrel. So am eager to see what Remington says about it.
Jevyod is offline  
Old May 18, 2012, 08:21 AM   #10
243winxb
Senior Member
 
Join Date: July 26, 2011
Posts: 1,051
What is the exact brand, bullet style, number of the "factory" ammo? Was it purchased at a gunshow or sporting goods store?
243winxb is offline  
Old May 18, 2012, 10:05 AM   #11
Jevyod
Senior Member
 
Join Date: May 5, 2012
Location: Pennsylvania
Posts: 105
The worst were Winchester 140g and 150g Ballistic Silvertips purchased at Dicks. I also bought some Federal 160g and some Remington 150g. I dont remember exactly where I bought those but I know they were local sporting goods stores. I never buy ammo at Wal Mart.All of the above caused some issues when chambering like having to force the bolt closed.
Jevyod is offline  
Old May 18, 2012, 09:03 PM   #12
wncchester
Senior Member
 
Join Date: December 1, 2002
Posts: 2,832
I said: "First, no weapon cares where the bullet nose hangs in space, all that matters is the jump before the bullet hits the rifling."

You said: "Sorry to disagree with you, but I must differ."

Facts are facts; disagree as you like, I don't mind.
wncchester 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 02:59 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2014 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Contact Us
Page generated in 0.09112 seconds with 9 queries