Working on a theory.... bullets that "work".

C

cinosbus

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Nov 5, 2008
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St. Charles, MO
#1
I've been reloading for a few years now, but I'm by no means an old hand at it - but I have spoken with a few guys that are.

A couple of them that have rifles that <span style="font-style: italic">shoot</span>are telling me that the jump to the lands is the biggest variable when it comes to bullets - as long as we're talking high quality bullets.

Since I like all of my magazine rifles to hold ammo <span style="font-style: italic">in the magaizine</span>, my seating depth is somewhat limited. I have noticed that the bullets that shoot "good" all seem to have about the same jump when seated to the same OAL. The ones that don't shoot very well tend to have a more "layed back" ogive - hence more jump to get to the rifling.

Anybody notice this? Agree? Disagree?

Why are all of the nifty polymer tipped bullets mfgd so that when they are seated, they have to make an Olympic record jump to the rifling? Is it because BC sells bullets?
 
#2
Re: Working on a theory.... bullets that "work".

Been there, done that, you're on the start of a long path.

If you find a bullet that's got the same ogive length relative to its OAL, you're way ahead of me.

More importantly, the key factor (for me) is neck tension, the less, the better. My criterion is that it is as light as possible, without being so loose I can rotate the bullet with two fingers firmly gripping the bullet.

Then, ream the flash holes, weight the charges, get really good at doing all of this <span style="font-weight: bold">consistently</span>, and the rest becomes somewhat less important. It probably also works, but it may not be worth the time/effort compared to actual range time. Range time is what it's really about, the rest is just the slave labor needed to make it possible.

Any technique you employ must be more valuable to your marksmanship activity than the comparable amount of time it subtracts from your range time. Simpler than that, it doesn't get.

Oh...; and the less centerfire ammo you make and shoot, beyond actually shooting a scorable or edible target, the better. Genuine Tactical Operators excepted.

The really Ohmigorshmickey serious marksmanship practice really works best with a .22LR... save the big gun for <span style="font-style: italic">real</span> targets....
 
#3
Re: Working on a theory.... bullets that "work".

What I'm getting at, is if the ogive is too far back on a bullet with a long nose, you can't get the ogive anywhere near the lands and still fit it in the magazine.

So I'm looking for bullets that are the same length or shorter in the nose than the ones that have worked.
 
#4
Re: Working on a theory.... bullets that "work".

cinosbus,
As a bullet designer, I'm familiar with the length constraint you're talking about. Here are a couple facts about bullets and rifles:

1. Bullets with longer ogives will have less drag, higher BC's, and superior performance.

2. Bullets with longer ogives will be harder (or impossible) to seat to magazine length, especially in rifles with long throats.

When the mag length 'problem' becomes apparent to reloaders, the natural reaction is; "why aren't more bullets made with shorter ogives"? Well, it's not just because higher BC <span style="font-style: italic">sells</span> more bullets, it's because higher BC is actually important to the ballistic performance of the shooting system, especially at long range.

So in light of the two facts above, rather than ask why we don't handicap bullets by making their ogives shorter, I ask: "Why are so many rifles made with such short magazine length/feeding length capacities"?

-Bryan
 
#5
Re: Working on a theory.... bullets that "work".

New bullets are cheaper than a new rifle
smirk.gif


I suppose the throat has to be long so that the gun will chamber and function safely with anything a person could shove in it (lawyers) and the magazine has to be short since the rifles and ammunition are being marketed with "short action" hype.

<span style="font-weight: bold">But since I'm not buying a new rifle anytime soon, got any hints on a hunting type soft point bullet that will work where a 175SMK works well</span>? Rifle is a Remington 700 5R Milspec .308 and it eats the 175smks and spits them wherever the crosshairs intersect as long as I don't mess it up before launch.
 
#8
Re: Working on a theory.... bullets that "work".

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Bryan Litz</div><div class="ubbcode-body">So in light of the two facts above, rather than ask why we don't handicap bullets by making their ogives shorter, I ask: "Why are so many rifles made with such short magazine length/feeding length capacities"? </div></div>

+308
 
#11
Re: Working on a theory.... bullets that "work".

Wow, that's a great article...

I was starting to think about that "arc" term. If it's in the brass prep I wonder if he's marking the cases somehow to know that it's oriented in the chamber each way for each shot.

As in, always align the black dot at the 3 o clock position.
 
#12
Re: Working on a theory.... bullets that "work".

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">But since I'm not buying a new rifle anytime soon, got any hints on a hunting type soft point bullet that will work where a 175SMK works well? </div></div>

Sierra lists the 180gr Spitzer Boattail (it is a Softpoint) as a ballistic match to the 175SMK/180-SMK, and I have used them in a pinch to sub for 175's for match shooting when the 175SMK was unavailable. They are grouped together with the same loads in the manual, along with the 180gr Spitzer, which is a Flatbase softpoint. Somewhat shorter, and maybe a better choice if the distances are not allowed to get really long, for mag feeding that would be my preference. Not precisely identical, the 180Spitzer BT's still stayed within roughly 1 MOA of my 175SMK zero at 300.

My experience is that they copper foul significantly more, so a wild guess would be that a softer jacket material is used in order to get better expansion behavior; yet another reason why SMK's are a ways down on my list as a hunting selection.

Greg
 
#13
Re: Working on a theory.... bullets that "work".

cool.gif
I had already bought a box of the 180gr BTSP Gamekings to try out... haven't shot any yet though.

I spent about 45min yesterday measuring bullets with a caliper and Hornady Comparator at the local reloading place (good thing they like me) and found out that the only common bullets with "short noses" similar to the 175SMK are the 180SGK mentioned above, the 165 and 168gr TSX <span style="font-style: italic"><span style="font-weight: bold">without</span></span> the plastic tip and just about any other softpoint <span style="font-style: italic"><span style="font-weight: bold">without a plastic tip </span></span>that I could get my hands on. If it had a plastic tip - Ballistic tip, SST, Interbond, Accubond, TSX tipped, Scirroco, etc, it had a very long jump to the rifling when seated to fit in the mag. I measured 150, 165, 168, and 180gr bullets. The best of the platic tipped are (ironically) the 180gr Accubond, but not by much, and my rifle didn't like them when I tried them the other day. I did not measure A-Maxes, but suspect they would be the same as the SST and Interbonds.

Looks like "regular old" bullets might be best for my purposes. If the Gamekings don't work out, I'm trying the 180 Hornady BTSP Interlock next as it too has a short nose (and .452 BC - FWIW).
 
#15
Re: Working on a theory.... bullets that "work".

My experience, If you're shooting a SAAMI chamber, and 1/2MOA is accurate enough for your tastes, the most important thing you can do to the bullets is simply load 'em. Measurements come under the 'too much info' heading, and really don't do much for you beyond giving you a headache.
 
#16
Re: Working on a theory.... bullets that "work".

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: cinosbus</div><div class="ubbcode-body">BTW - I'm not cutting my barrel off to 21.75" anytime soon...
laugh.gif
</div></div>

LOL yea thats a 100-200 yard BR trick. I dont plan on that either...
 
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