OAL problems with rem 700

[pwrlineman]

I purchased a used rem 700, 7mm mag and have started prepping some once fired brass to reload. I fired 17 rounds of hornady 154 gr sst, shortly after buying,and noticed that the bolt was hard to close but shrugged it off. The reloading manuals give a oal of 3.290 which is about what the factory hornadys are. However, The lead length seems much shorter and closer to 3.200. I have three factory hornady's left and when I close the bolt it leaves rifling marks on the bullet! I have tried to determine the lead length by inserting a case with a loose bullet but the bullet falls back into the case! What am I to do. I found a couple of references on the web about this problem, but none of them seem to explain the problem. I would really appreciate some advice. Thanks

 

[hntbambi]

Does the gun have a custom barrel?
The previous owner could have had it rechambered with a shorter throat. You can smoke a bullet with soot from a candle or butane lighter to see where the lands are. Carefully insert the cartridge and carefully guide it out to see the marks. Seat the bullet a little deeper and repeat until you find the bullet just kissing the lands. That is 0. Adjust your seating die to give you the desired jump.

Another way of measuring the disance to the lands is to take a resized case and use a thin fine blade saw or cutoff wheel in a dremel and cut slots in the neck of the brass. This will allow you to seat the bullet by hand, chamber the case, eject it carefully. The slotted neck will give enough tension to hold the bullet allowing you to measure the max COAL for your gun and bullet combo.

Different bullets will have different bearing surfaces so its not interchangeable from a 154 gr round nose, spire point, Interbond, or SST. Each one should be measured for the COAL distance.

 

[just_a_hunter]

One of these

http://www.midwayusa.com/product/570611/hornady-lock-n-load-overall-length-gage-bolt-action

with one of these

http://www.midwayusa.com/product/48...dified-case-7mm-remington-magnum?cm_vc=OBL7_1

and one of these

http://www.midwayusa.com/product/746974/ptg-bullet-comparator-22-24-25-26-28-30-calibers

all combined with one of these

http://www.midwayusa.com/product/119623/frankford-arsenal-dial-caliper-6-stainless-steel

Will not only tell you everything you need to know about this rifles lands depth but also any other rifle you have. Like stated above bullets aren't interchangable when it comes to OAL.

Its a little spendy I know, but from here on out you'll only have to purchase the modified case.

If times are tight right now like they are for most of us, PM me your address and I will let you borrow my stuff to figure out your rifle. I have everything you need minus a caliper.

Good luck,

Todd

 

[mtmuley]

I bought Stoney Point measuring tools. Easier than messing around with other methods. Once you have your dimensions for sizing and seating, it's repeatable and perfect every time. Does the bolt close stiff on the factory rounds? Are the once fired rounds from your rifle? mtmuley

 

[Cahunter805]

That is a very short oal for a 7mm magnum. I can't imagine someone rebarreling a rifle that short. You need to measure the lands with whatever bullet you plan on loading. I usually start .010 off the lands with all bullets besides monolithic.

 

[pwrlineman]

The once fired rounds I mentioned were factory hornady 154gr sst. I purchased them to test the rifle and then use the brass for reloading. I noticed how tough it was to close the bolt, but did not think much about it at the time. The barrel does not appear to have a custom barrel, but it does have a muzzle break. The factory ammo is very close to the 3.290. When I use a loose case with a 154 gr inter bond/sst, the correct oal length appears somewhere near 3.2 but the bullet falls back into the case. I'm not sure I can reload it to keep off the rifling and still have enough bullet out off the case to prevent it from falling into the case?

 

[just_a_hunter]

>The once fired rounds I mentioned
>were factory hornady 154gr sst.
>I purchased them to test
>the rifle and then use
>the brass for reloading. I
>noticed how tough it was
>to close the bolt, but
>did not think much about
>it at the time. The
>barrel does not appear to
>have a custom barrel, but
>it does have a muzzle
>break. The factory ammo is
>very close to the 3.290.
>When I use a loose
>case with a 154 gr
>inter bond/sst, the correct oal
>length appears somewhere near 3.2
>but the bullet falls back
>into the case. I'm not
>sure I can reload it
>to keep off the rifling
>and still have enough bullet
>out off the case to
>prevent it from falling into
>the case?


Time to find a gunsmith.

Todd

 

[440sixpack]

I agree find a gunsmith. if factory rounds are too long someone has done something silly.

If your headspace and everything else checks out you can deal with the short throat by adjusting your OAL to fit .











Stay thirsty my friends

 

[NoDoe]

I would sure like to know the answer to your problem. Please post.
Don