Bullet setback after chambering?

[Jmanwit]

Hello all. I just set up my RCBS Single-Stage press after it sat in my garage for a while. I bought a Remington 700 SPS Varmint recently and decided it was time to stretch it's
accuracy potential.
Here is the issue. I bought the LEE dluxe die set, and full-length sizing is not an issue, and after I got my Bullet depth set (at 2.800), it seemed fine. Until I chambered a round. It felt a little tight going in, and after I measured it with my calipers, I ended up measuring 2.700ish.
Now,my first instinct is maybe my weapon has a short(er) chamber, but I dont see how that would pass Remington CQ.
Any ideas out there guys? THanks in advance,
Justin

 

[Jmanwit]

Re: Bullet setback after chambering?

I should say, the bolt went in towards the chamber no problem, but the actual closing of the bolt is where it seemed like there was excess pressure needed.

 

[armorpl8chikn]

Re: Bullet setback after chambering?

You seated your bullet depth at 2.800, which I can only assume is OAL to the tip of the bullet. You chambered a round and it chambered hard and you extracted the cartridge and found that your OAL is now 2.700" "ish". Have I got this str8 so far? That means you jammed the lands .100" and your chamber seated the bullet farther into the case. First of all you do NOT use OAL to determine seating depth. You need to use a measurement determined from the ogive of the bullet. This is simple reloading 101 stuff that a good manual or decent book on reloading should teach you. You can get by with a cheap bullet comparator from Sinclair International that looks like a hex nut. I will not post the link for you because you can Google it yourself just as easy as I can. You can get by fine with this comparator and a fired and resized case(minimum resizing is best here) with a split in the neck up to the shoulder junction of the neck. You will need a small pair of vce grips with padded jaws to hold the neck tight so the bullet doesn't slide down further in the case for measuring with calipers and comparator. I think I will do a video on this as soon as I can since this seems to come up in this thread about once a week.

 

[Jmanwit]

Re: Bullet setback after chambering?

I appologize, but in all my research, you are the first to even use the term ogive. I will have to look at it again. Apparently my Sierra loading manual is missing a few pages. If there are any, what is the best online reloading reference?

 

[BBeyer]

Re: Bullet setback after chambering?

The ogive is the shape of the curved part of the bullet and expressed by a single number, the higher the number the more pointed the bullet will be. I believe that armor is refering to a spot on the bullet where the bullet comparator hits the pointed end of the bullet, which is not the case.

 

[Jmanwit]

Re: Bullet setback after chambering?

So a bullet comparator is necessary equiptment? Again, I have never seen people mention that piece of equiptment before, so I am not sure. Also, any word on decent online reloading resources?

 

[armorpl8chikn]

Re: Bullet setback after chambering?

No need to appologize you have done nothing wrong. I do not know any good online references as I have been doing this many many years. Go to 6BR.com and dig around over there and see if you can't come up with some good info.
The best reference is some crotchety old dude that lives near you that shoots every weekend and has neevr shot more than a handful of factory rounds. If you can get him to let you look over his shoulder for a few hours you will learn fast and well. If you learn everything on the internet your tutellage will be rife with mistakes and head scratching.
I said a good manual SHOULD teach you these things, sadly most probably do not. Get a comparator from Sinclair so that you can at least measure ogive length of your cartridge this will give you a huge advantage over what you are doing now.
There is also a method in which you can smoke the bullet with a candle and continue to seat the bullet, chamber, seat, smoke, rechamber etc until you no longer touch the lands that is really old school but it works fine. being EXACTLY a certain distance off the lands is not as important as one may think. Get about .010"-.015" off the lands and develope your load, it will work just fine.
Any time you jam the lands your cartridge will be hard to chamber unless your neck tension is very light.

 

[Jmanwit]

Re: Bullet setback after chambering?

Thanks man. So it was indeed my lands pushing the bullet back that I felt. Roger. I gotta track down an old reloader around here! Sadly, I moved away from the guy who would show me all these things. He gave me a crash course shortly before leaving California, and GAVE me the RCBS press, 4 die sets, powder primer etc. He taught me a lot (compared to what I knew before) and I call him every now and again for stuff, but he is a little busy today, so I couldnt.

 

[armorpl8chikn]

Re: Bullet setback after chambering?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BBeyer</div><div class="ubbcode-body">The ogive is the shape of the curved part of the bullet and expressed by a single number, the higher the number the more pointed the bullet will be. I believe that armor is refering to a spot on the bullet where the bullet comparator hits the pointed end of the bullet, which is not the case. </div></div>

You are correct. But I have always referred to it as measuring from the ogive. In reality you are measuring from the nexxus of the ogive and the major bullet diameter which is where the bullet will first contact the lands.

 

[BBeyer]

Re: Bullet setback after chambering?

I realize that most of the guys on this site use the term the same way you do, the gentleman asked about ogive and I just let him know what it is.
I dont know about your measuring tool but I have a stony point [I believe] that measures a spot on the ogive at a point where it is approx. .297 inch. This is not the major diameter but could be the point where the bullet first meets the lands. I do not know if the bullet had a datam line, as the shoulder does, but if it does I would imagine that the spot that the measureing tool contacts the bullet would be it. Thinking about it I dont imagine it would be practical to have a datam line on anything as flexable as a bullet.