Mag surgery. A plan with potential or pitfall?

OK, back to what I thought we were discussing- single direct loading.

Pond, that's either laying a round on TOP of the follower without seating it INSIDE the mag, or just sliding one directly into the chamber.
Either way allows you to adjust your OAL beyond the physical limits of your magazine, if you can tolerate using your rifle as a single-shot.

By "close" I was referring to closing the BOLT.

What your extractor SHOULD do is allow the bolt to close fully on a round inserted into the chamber, acting as a push-feed design when used in that manner, as opposed to a controlled-round feed.

Your extractor should slip, slide, or divert itself AROUND the rim of the cartridge case to do this.

You don't need to spend time Internetting or messing with snap caps.

Just carefully insert a live round into your chamber, keep your muzzle in a safe direction, keep your finger off the trigger, and close the bolt fully.

It'll either close or it won't.
Mine does.

Many modern commercial Mauser-style extractors are modified with a bevel, as Jim says, that lets the extractor override the case rim.
Denis
 
This thread calls to mind a conversation I had on Friday. My brother in law has built some rifles using Mauser actions. He is quite particular that anyone shooting these guns place a round into the mag to be picked up by the bolt to make sure the extractor isn't taxed by flexing to snap over the case. When we went shooting this week he elaborated a little, specifically mentioning that it can be hard for him to find replacement extractors if one breaks.

You are shooting a recently-built rifle, not something using a 100+ year-old action. Parts availability may not be as a big a problem. My recommendation would be to contact CZ to ask whether the extractor in that gun is made to close over rounds loaded directly to the chamber, and to find out how much replacement extractors cost. It might even make sense to buy spares if you do decide to load longer OAL rounds that you can't feed through the magazine, in case you do break or wear one out.

If I had a supply of mags, I might be tempted to try to modify one to see if I could get reliable function after cutting. Since CZ550 mags are $62.99 at MidwayUSA, I might not be too eager to stock up. Maybe they are cheaper in Estonia.

Quick question: If you were able to doctor a mag so that it could take longer rounds, are you sure that you wouldn't then run into clearance problems in the mag well? It would be one thing to waste a mag, and another, more expensive thing to damage the action.

Good luck!
Tom

PS On a clear day, can you see Finland? :)
 
I'll have to experiment with my snap-cap. At least aluminium is way softer than bolt steel, so if one is going to go, it can be the cheap snap-cap.

Brass is softer yet, but the end of the extractor on my 1911, which was made of steel, I am quite sure ...... snapped right off. It just was not designed to do that.

I am not sure the Mauser extractor was not designed to flex a bit .... but looking at it, it appears the rounds are supposed to slide up from the bottom.
 
The Mauser CRF extractor in original military form was designed for the case rim to slide up inside the extractor, not in front of it. That's the controlled-round-feed.
There's not much flex in the design.

I have a 98 Mauser pattern that will not close on a direct-feed.
The CZ is built to handle it at least sporadically.
It's a different situation from the 1911 pistol & not a direct comparison.
Denis
 
Maybe they are cheaper in Estonia.

Haha. Hahahahaha!! OooooHahahaha!! Ooooh, my tummy hurts... That was a good one! :D;)

Seriously though: They run about twice that €112 for a 4 round mag...:(

Quick question: If you were able to doctor a mag so that it could take longer rounds, are you sure that you wouldn't then run into clearance problems in the mag well? It would be one thing to waste a mag, and another, more expensive thing to damage the action.

Well, I suppose it was initially meant to be a cheap Integral mag conversion. Keeping that mag in situ would have given the side walls support and if I had taken back the feed tangs, I could have loaded from above, although the scope rings would mag it a bit tight.

Buying a replacement trigger guard assembly from another CZ550 model that has an integral mag, such my previous CZ550 Standard was/is another option. If I can single load safely than I can play with seating closer to the lands. If that yields a particularly good load, then I may decide all these changes are worth it.

PS On a clear day, can you see Finland?

Probably not. I never have. It is 50miles north and neither country has high-rising terrain. But I do see a daily boat load of Finns: alcohol is significantly cheaper in Estonia (something had to be)!! So they come over to stock up. Some of them get back on the boats slightly worse for wear!!

You don't need to spend time Internetting or messing with snap caps.

I have a plan to slip a round into the chamber, but tuck the base in the mag and see if it will pick up the cartridge correctly. I still prefer to use a snap cap. For me that is what they were designed for: chambering in an environment where you don't plan to fire. It just makes me a little uncomfortable.

I certainly don't want to start using parts in a manner they weren't designed to, so if this mag method doesn't work, tough luck for me!
 
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I've just checked my mag length at it runs at 72.55mm. My rounds are seated to 72.35mm.

So that is a miserly 0.2mm of clearance. I fear any less and I will have feeding issues.
 
I suggest:

Typically,while you cannot load a full mag with over length rounds,one round of over length can usually be loaded into the mag as the bullet tip is up in front of the feed ramp.

So,likely you can simply single load one round in the mag,and then as you close the bolt the round will feed up under the extractor in proper CRF fashion.

I suggest firing a couple of 10 round targets to get a good feel for how much the difference in seating depth is improving accuracy.

Based on your results...remember from the point of aim the the point of impact it is the radius ,not the diameter,of the group increase that matters.
What? Suppose you had the perfect zero MOA one hole rifle,loading off the lands.Suppose loading to mag length messed your rifle up to a .500 MOA rifle.

If you were shooting at this period "." at 100 yds,the worst shots at the edge of the group would be off by a maximum of 1/4 inch.

How close can you hold?
 
I don't know how you plan to insert a round into the chamber and tuck the base into the magazine.
It can't be both.

Snap caps are built for pulling triggers, not for testing feeding or OALs.

If you want to see if your rifle will close on a live round, put a live round in the chamber & close the bolt.
The process is simple & takes seconds vs days of discussion in a gun forum.

I also checked a CZ 550 Magnum in .375 H&H here. It has the beveled extractor & it'll close on a direct feed.

I seriously doubt yours would do anything different.

You're greatly over-complicating this whole thing.

DO NOT MUTILATE YOUR EXISTING MAGAZINE. It's fabricated to the tolerances it comes with for good reasons. It's designed to certain dimensions not merely to contain the cartridges, but to keep them in one location & present them consistently to the bolt for feeding. You remove fronts, backs, sides, or alter "boundaries" & you compromise all that.
Remember those rounds move fore & aft under recoil & need to be confined to a specific limited range of travel.

YOUR RIFLE WILL CLOSE ON A ROUND DIRECTLY FED INTO THE CHAMBER, AS OPPOSED TO FROM THE MAGAZINE. It is designed to allow that. You do not need snap caps to test it, and the best way you test a given process is to use the actual process components that will be used, as opposed to simulants.

All of this can be simplified by just doing what thousands of other shooters who reload with emphasis on getting as close to bore rifling as possible do: Simply work up your chosen utility load with the bullet seated as far out as you can, while still meeting the physical confines of your factory magazine and retaining reliable feed & function.

If your end goal is strictly a target rifle, then consider buying a target rifle.
If your end goal is a decently accurate varmint gun, you should easily be able to tune a varmint load that'll give you an inch or less at 100 yards while staying with an un-altered magazine and cartridges that'll fit & function within & from it.

The CZ 527 in .223 here has gone 1 9/16 inches for three at 100. Not spectacular, but not horrible, and it's not a varminter.
I'd expect better in a heavier barrel.
My Weatherby Vanguard has gone down to half an inch at that distance, as a dedicated coyote/varmint gun.
Those best groups with both rifles were achieved with factory ammunition.
They MIGHT do better someday if I take the time to work on handloads for them.

How much accuracy do you need? How much are you getting now? What kind of shooting does that rifle need to do?

I'd suggest the possibility that your energy would be better spent on working up the most accurate load you can with an OAL that fits your mag, quit worrying about getting into the rifling, put good glass on the gun, and learn to shoot it.

Altering the rifle drastically so you can get closer to the rifling is obsession over something that most likely would not result in any hugely useful accuracy gain for you, but would certainly result in a reduction of function.

As for the single direct-chamber loading issue, if you think you have to persist in experimentation with OALs along those lines, just stick a live round in the chamber (COMPLETELY in the chamber, not half in it & half in the mag), and close the bolt on it. Extremely simple, extremely quick, and the gun will neither explode in your hands nor spew extractor parts in all directions.

I would not advise single-loading this way as a lifetime practice even in a Mauser-based action that allows it, but the gun can handle it for a bit without damage or danger.

If you're concerned about the gun firing itself while you direct-feed a round into the chamber, both 550s here (although their safeties do differ with one being a two-position & the other being a three-position) will allow the safety to be activated ONCE YOU OPEN THE BOLT. That means you can open the bolt, activate the safety, directly insert a round into the chamber (bypassing the mag entirely), and close the bolt to determine once & for all if it'll allow direct feeding, WITH THE SAFETY STILL APPLIED.

Denis
 
So,likely you can simply single load one round in the mag,and then as you close the bolt the round will feed up under the extractor in proper CRF fashion.

This is a very nice option which I had not considered. Thanks!!

How close can you hold?

I'm ashamed to say I don't know what you mean by this!! :o If it helps and relates to your question, I have not zero'd my scope to any of my new loads. I just know that they all shoot from 6" to 10" high from POA. So relative to the POA, the hits are miles away. In relation to one another they are so-so.
My best shooting gave a group with about an inch and a half or so. I know I am the weak link there.

Snap caps are built for pulling triggers, not for testing feeding or OALs.

OK, but I did try and I was able to quite comfortably slip a snap-cap into the chamber then push the head down and back into the mag so the mag tabs hold it. The bolt then comes forward and the rim of the case slips nicely under the extractor.

Simply work up your chosen utility load with the bullet seated as far out as you can, while still meeting the physical confines of your factory magazine and retaining reliable feed & function.

This at least I have managed to with my 72.35mm OAL. I still want to try an OAL closer to the lands as I measure it with the chamber gauge, if nothing else than trying to explore this aspect of reloading and see exactly how more accurate I can make these and other cartridges.
I don't doubt what you've described about the extractor and direct feeding, but I now know that I can easily feed from the mag as I described, so that gives the option of not jamming the bolt onto the back of the case.

If you're concerned about the gun firing itself while you direct-feed a round into the chamber, both 550s here (although their safeties do differ with one being a two-position & the other being a three-position) will allow the safety to be activated ONCE YOU OPEN THE BOLT. That means you can open the bolt, activate the safety, directly insert a round into the chamber (bypassing the mag entirely), and close the bolt to determine once & for all if it'll allow direct feeding, WITH THE SAFETY STILL APPLIED.

That is a worthy point that I may turn to, but I still will try to avoid straining the extractor as a general rule. There's no point if I find a method that works without needing direct feed.
 
Do you know what the chamber is?

Do you mean with the chamber length gauge?

If so, then yes: with the Hornady Amax my max OAL is 73.36mm, so I am seating 0.9mm off the lands as restricted by the mag.
That is 0.035" off the lands.
 
No, I just wanted to be sure we're talking about the same part of the gun when we say "chamber".
Denis
 
I suggest:

Typically,while you cannot load a full mag with over length rounds,one round of over length can usually be loaded into the mag as the bullet tip is up in front of the feed ramp.
So you suggest loading at least two different OAL's, and then using them both at the same time?

Yeah, no chance of a problem there
 
So you suggest loading at least two different OAL's, and then using them both at the same time?

Yeah, no chance of a problem there

I think the idea was to make my 4-rd mag into a 1-rd mag by loading only a single, rather than loading different cartridge lengths.

That round can afford to have a longer OAL than the mag would normally allow because the upper-most round in the mag is angled in such a way that the bullet tip is pointing up, outside the confines of the mag wall.
 
No,Snyper,I'll try typing slow so you can keep up.

Mr Pond understood.

I suggested he could feed a batch of his over mag length ammo by loading only one round into the mag from open bolt.This gets past the distraction of whether the extractor will snapover.Just load one at a time,and CRF them up from the mag.

Shoot enough to establish the group/accuracy of the long load


Then compare the accuracy of the long load to ammo that will fit in the mag and feed.

Based on the results,evaluate whether the rewards of long seating the bullets made all the trouble of long seating worthwhile.

I have no idea where you came up with the idea of mixing the rounds in the magazine,maybe you were just looking for something to be critical about?

Mr Pond,my question about how well you can hold was not to disrespect your marksmanship.The shooter,the ammo,and the rifle all come together to define the package.
If the ammo ,short vs long,results in a 1/2 in bigger group at 100 yds,that only means 1/4 inch farther from the perfect center of your point of aim at 100 yds.
If you have progressed to become an exceptionally good marksman(far better than myself) then that extra 1/4 in is a limitation.

If it is for benchrest,that is one thing.If it is for shooting crows or lurking lager cans or bullseyes from shooting positions,how much of % factor is the short vs long ammo?

Respectfully,once your ammo/rifle are shooting to a practical accuracy level,shoot! For most of us,the greatest possibility to improve our targets is in shooting skill rather than obsessing the minutia of bench rest ammo technique.
 
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I have no idea where you came up with the idea of mixing the rounds in the magazine,maybe you were just looking for something to be critical about?

Maybe it was because you mentioned loading a whole mag:

Typically,while you cannot load a full mag with over length rounds,one round of over length can usually be loaded into the mag as the bullet tip is up in front of the feed ramp.
 
Really?Where?

I did say "You cannot load a full mag with over length rounds"
Does that say load a full mag???No.
I did say you can typically load one over length round in the magazine.The whole point was to get past the distraction of push feed/extractor snapover by single loading in a controlled round feed fashion.

Check the next line where I say to load one round in the magazine,then as you close the bolt...

You own the rest.
 
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