Why Are So Many Rifles Magazine/Feed Mechanism Limited?

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JDinFbg

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For several of my rifles, loads that will fit the chamber and provide optimum bullet jump (around 0.015” – 0.020”) end up being too long to fit in the magazine or feed through the mechanism. This severely limits my choice of bullets I can try and results in cartridges that have, in my opinion, excessive bullet jump. Why did manufactures design rifles that are limited in this regard?

As one example, I have a Model 43 Winchester in 218 Bee. I’ve tested three 40 grain bullets in this rifle – Sierra Hornet, Hornady V-Max, Berger FB Varmint – and all three if loaded to provide a 0.020” bullet jump end up being too long to fit in the magazine. If loaded to fit the magazine, the Hornady and Berger bullets end up with the ogive of the bullet inside the mouth of the case. This obviously is not acceptable. Even the Sierra bullet has to be loaded to where is has far more bullet jump than desired if I want it to fit in the magazine.

Another example is my 94 Winchester in 30 WCF. My chamber would allow the Speer 150 grain FN bullet to be loaded to an O.A.L. of 2.631” to provide a 0.020” bullet jump. Based on tests, I can load cartridges to an O.A.L. of 2.607” and achieve feeding through the mechanism, but end up with a bullet jump of 0.044”. If I were to seat bullets to the cannelure (2.542” O.A.L.), the bullet jump would be 0.109”. Luckily, I have developed a loading technique that does not require me to crimp the bullets but avoids risk of bullet compression into the case.

So, to my title question? I would like all my rifles to be chamber-limited with respect to what I can load rather than being limited by the magazine of feed mechanism. What say you?
 
If it fits, it ships.

If a longer mag box is used, it can be possible to over-run your chamber, or over-run reliable feeding. So they leave mag boxes just a little over standard length for the action length and cut throats longer - and resultingly, if it fits, it ships.
 
To eliminate some of this no fit in the mag stuff, I purpose built a long action bolt gun on 308, I like Bergers seated way out to eliminate the less than optimal bullet leade engagement and this arrangement allows me all the flexibility nessasary to do what I want.
 
For several of my rifles, loads that will fit the chamber and provide optimum bullet jump (around 0.015” – 0.020”) end up being too long to fit in the magazine or feed through the mechanism. This severely limits my choice of bullets I can try and results in cartridges that have, in my opinion, excessive bullet jump. Why did manufactures design rifles that are limited in this regard?
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They make them to fit all loads, not yours. You could face off the barrel a bit and rechamber so your bullet is in contact with the lands and have more than enough room in the magazine. Just means some combinations won’t work at their intended OAL.

In other words, made to fit your bullet would “limit” the rifle, they open it up so lots of different things will work without jamming into the rifling.

So, if you are using the bullet on the right, you might have a jump loaded to magazine length but if you loaded the bullet on the left to magazine length, it might not even chamber.

EE70A1E1-70FB-4A48-83DA-9F67004CF407.jpeg

Pretty big difference between the point of contact on the ogive vs location of the tip, that would limit OAL for a mag.

BA505EA8-14C8-47B6-8018-4507E6048C15.jpeg 3D75CB42-1DFC-43A4-B141-161E606A8447.jpeg
 
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Treating new hunting guns and "modern sporting rifles" like target rifles is a fairly recent aberration. It can work pretty well, barrels and bullets are better than they used to be, if you get good ones on the mass production quality curve.

But bullet jump in a .218 Bee made not later than 1957 was not even a glimmer in the designer's mind.
And in a .30-30? Puhleeze
 
i believe defiance makes a mid length action between short and long (xm maybe?) and you can get MPA stocks for it and i forget who makes the magazines. i kinda wanted one for my 260AI
 
Jim Watson said:
Treating new hunting guns and "modern sporting rifles" like target rifles is a fairly recent aberration.
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I'm not sure I would agree with that assessment. I shot hunting rifles in benchrest competitions (Hunter Class) back in the late 1960's and early 1970's. The goal then, as it is now, is sub-MOA accuracy. Long bullet jumps usually don't provide sub-MOA results. If you are trying to make neck shots on a deer at 100 yds. or vaporize a prairie dog at 300 yds., you need sub-MOA capability.
 
I tend to agree. The old coyote hunters and prairie dog hunters who raised me were doing the same things I’m doing today, 30yrs ago, and they weren’t young nor new to it even then.

But, culturally, these “Varminters” were a niche subset of hunters, a silent minority which was left to its own devices for a long time. But sometime around a decade ago, certainly not 15 years ago yet, I started getting phone calls from the “deer hunters” who thumbed their noses in years past when I’d invite them to go predator calling, or who would roll their eyes when I mentioned the load development I did for my hunting ammo... they started calling to ask about making their hunting rifles more accurate, about reloading, and about opportunities to get out and shoot beyond the half of box of ammo they fired each year in the weeks before deer season...
 
JDinFbg said:
Long bullet jumps usually don't provide sub-MOA results.
Click to expand...

I've had no problem getting sub-MOA results with bullet jump as much as .250". The only thing I can say for sure is that the longer the COAL for a given bullet, case and powder combination, the greater the amount of powder that can fit in the case.

I've found that Federal GMM, Federal Trophy Copper, and Hornady Match ammunition shoots very well in numerous rifles with all manner of bullet jump.
 
@taliv, that is one of the theories put forward to explain why Federal GMM shoots so well in so many rifles. Litz talks about it but I don't think anyone actually knows why. I've read some articles suggesting easier or better alignment is possible with tangent ogives so they're less sensitive to jump.

Here's a secant bullet that might prefer more jump to less jump.

https://bergerbullets.com/vld-making-shoot/
 
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The U.S. Military .308 sniper rifle built on a Model 700 receiver. Aren’t they long actions even though they are using a short action cartridge?
 
JDinFbg said:
I'm not sure I would agree with that assessment. I shot hunting rifles in benchrest competitions (Hunter Class) back in the late 1960's and early 1970's. The goal then, as it is now, is sub-MOA accuracy. Long bullet jumps usually don't provide sub-MOA results. If you are trying to make neck shots on a deer at 100 yds. or vaporize a prairie dog at 300 yds., you need sub-MOA capability.
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Walkalong said:
Sure, some folks were doing it, but the vast majority were not. Load and shoot, be happy

Not to mention some bullets can jump a long way can be very accurate.
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Those have been my observations. I started this journey in 2000ish, while still in highschool and knew quite a few people who reloaded, but no one cared about BC, bullet jump, or even sorting brass.
There were also the odd few who were real gun nuts, and took the time to explain all that too me. But were talking about 2 guys, both of whom I saw once or twice a year when they hunted our property.
The vast majority of people I knew tho were (and still are) factory ammo users, even guys that reload.
cdb1 said:
The U.S. Military .308 sniper rifle built on a Model 700 receiver. Aren’t they long actions even though they are using a short action cartridge?
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I thought the newer ones were short action.
 
I know m24s were built on long actions...thought at least some of the m40s were shorts.....this is all outside of my normal range of knowledge tho so I could be way off base.
 
From Wikipedia: “The primary difference between the Army and the U.S. Marine Corps rifles is that while the U.S. Marine Corps M40 variants use the short-action version of the Remington 700/40x which is designed for cartridges having an overall length of 2.750 inches (69.85 mm) or less (such as the .308 Winchester/7.62×51 mm NATO), the Army M24 uses the Remington 700 Long Action.”
 
I had my first experience with throat length vs. seating depth back in 1980 when I had my first custom rifle built.I had to explain to the gunsmith who chambered it for me why I was so picky about how long the throat was.Back then,the Sierra Game King was one of the more accurate hunting bullets that was readily available.I seated one in 280 brass just deep enough for the base of the bullet to be at the neck/shoulder juncture and I made sure the jump was around .020.That gave me all the powder capacity it had,but kept the bullet in the neck of the case good.That rifle shot very good.I took that barrel off this past summer and it went from a 280 to a 280AI.The new barrel was chambered by Shilen and they got it perfect for the 168 grain Bergers I shoot in it.I agree with the magazine length being a safety feature to keep bullets out of the lands.I think Remington took it too much to heart when they chambered barrels for the 308 class cartridges in their short action 700.I have one that the throat is .115" longer than the magazine length.Weatherby rifles have a lot of freebore in some of their chamberings and their rifles shoot well.
 
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