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.32 S&W KF vs Imported ammo

Posted: Thu May 29, 2008 1:04 pm
by Olly
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Just happened to compare the two bullets - KF and Magtech (Made in Brazil and imported by USA).
Both bullets are : .32 cal. S&W L for revolver

Apparent comparison indicates the difference in the quality of brass and also the quality of lead bullet-head. The crudeness of the KF is visible.

Point A : See the thickness of the lead band. In KF it is broader. In Magtech it is much smaller. The logical result is that when fired, it is going to scrape through the barrel much harder and much longer. Also when compared between different rounds of KF itself, this band is not consistently maintained. In some it is more defined, in some it is less.

Point B : The grove just above the rim of the shell. Don't know the significance of its presence (Magtech) or absence (KF). Don't know of other foreign brands, whether they have it or not.

Point C : The bullet-head in Magtech is longer and more pointed than KF. Here also I can't guage the effect....

Posted: Thu May 29, 2008 1:08 pm
by Olly
Now, fitting the IOF bullet head into the barrel of a IOF .32 revolver, without any pressure.

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Posted: Thu May 29, 2008 1:10 pm
by Olly
Now, fitting the Magtech bullet head into the barrel of a .32 IOF Revolver

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Re: KF vs Magtech

Posted: Thu May 29, 2008 2:18 pm
by TwoRivers
Olly, Point B: The groove above the rim, and it's deeper than needed, simply serves to eliminate any fillet, and allows the case rim to seat flush, even if the chamber mouth should be sharp cornered. Some maker use it, others don't. Other than that, the proof of the pudding is in the eating. You are not going to learn anything about how good the shells are by this comparison. Shooting, from a rest; and chronographing, are the only ways to tell. Bullet diameter outside the case, unless it's oversize, tells you nothing, what's hidden inside counts. Cheers.

Posted: Thu May 29, 2008 4:20 pm
by Olly
The question is : In Point A, due to the extra-thickness of the lead band and the difficult fit into the barrel of the revolver, each round fires differently, resulting in a 'generous spread' all over the target.
I agree that the round must be a tight fit to rotate it, but should it be so tight so as to slow it down ?
Even the lead not exiting the barrel is not unheard of... AC will confer with me.. ?

Secondly, the uneven thickness and lack of uniformity is resulting in the revolver jamming after firing 2-3 rounds. Probably it jams whenever a very unusually constructed round come up and gets fired. Sometimes on a lucky day... even after firing 6-10 nothing happens and the revolver behaves normally. In such cases, even target acquisition is quite accurate... so much so that once Dev Uncle even put in 2 bullets into the same hole... :roll:

Re: KF vs Magtech

Posted: Thu May 29, 2008 11:59 pm
by TwoRivers
Olly: From your de.scription of the problem it sounds very much like very poor and variable ammunition. Which, incidentally, has nothing to do with the exposed driving band of the K-F bullet. If the bullet doesn't leave the barrel, then the case simply had no powder; the primer has enough force to drive the bullet into the barrel. The important consideration for accuracy in a revolver is the relationship of the diameter of the mouth of the cylinder chambers to the bullet and bore diameters. The bullet is immediately expanded, or sized down, to whatever diameter is available, and then sized down again as it enters the barrel. You are not dealing with air guns here; a bullet, whether lead or jacketed, is expanded immediately upon firing to the diameter of the chamber leade, slightly larger than the groove diameter. That way, obturation is assured. A bullet too large will result in a pressure spike upon firing, but once sized down to the particular barrel behaves like any other. "Jamming" in a revolver is usually caused by primers backing out and dragging on the recoil shield. The cause coud be high pressure, rough chamber, soft brass or primer pockets too large, or too much headspace. If the jamming occurs after the same chamber has been fired, the problem is likely to be the chamber. If the jamming is random, it's the ammo. How far a bullet enters the muzzle tells you nothing about how that particular ammo/gun combination will perform. If you knew what the bulle/bore/groove diameters are supposed to be, and had measured them, it might give you some clues. Only firing from a machine rest, and a chronograph, will give you the accuracy potential. Cheers.

Posted: Fri May 30, 2008 2:15 am
by shahid
The extra lead on the rim will lead to moe fouling in the barrel. Of course the quality control and batch control of IOF leaves much to be desired.

How many grains is a .32 S & W Long revolver bullet ? And what Me ?

Re: KF vs Magtech

Posted: Fri May 30, 2008 3:49 am
by TwoRivers
Bullet weight is 98 grains, MV about 700 fps and ME about 115 foot ponds. Doubt very much that that little bit of unlubricated exposed lead would cause any problem, provided the rest of the bullet is lubricated. Nor did Olly mention a severe, or any, problem with leading of the barrel. Cheers.

Posted: Sat May 31, 2008 3:39 am
by shahid
Really depends on how many IOF rounds he fired through it. If just 10 / 12 rounds it may not be very apparent. But if he fired more than 50 to 60 on the range which is the unlikely case then it would appear.

I would wait and watch as more IOF cartridges are fired in this revolver over a short period of time, it is going to appear very soon.

The problem of misfiring is also not uncommon in IOF Pistol. .32 ACP cartridges, same might apply for revolver cartridges too. Misfire rate is close to 3 %.

Posted: Sat May 31, 2008 7:15 pm
by Olly
I haven't had a single KF misfire till date ! Total output thru this gun is around 60-70....

I am afraid to spoil the groovings in the barrel due to the extra wide band of lead on the KF. Wonder if the IOF barrels can withstand such whipping from the slugs...

Re: KF vs Magtech

Posted: Sat May 31, 2008 8:46 pm
by TwoRivers
Olly: Can you see me rolling my eyes, shaking my head, and pulling out my hair? What is that barrel made of, pot metal?

Posted: Sat May 31, 2008 9:22 pm
by mundaire
TwoRivers";p="44795 wrote: Olly: Can you see me rolling my eyes, shaking my head, and pulling out my hair? What is that barrel made off, pot metal?
:mrgreen:

Re: KF vs Magtech

Posted: Sat May 31, 2008 9:34 pm
by cottage cheese
TwoRivers";p="44795 wrote:Olly: Can you see me rolling my eyes, shaking my head, and pulling out my hair? What is that barrel made off, pot metal?
probably cast out of solder :mrgreen:

Posted: Sat May 31, 2008 11:50 pm
by mundaire
All said and done, from what I hear IOF does at least use quality steel... they being one of the only ones who have successfully chambered the SMLE action in 7.62 NATO/ .308 Win, based on the fact that they used superior steels for the job! That of course was the 1960's, one gets the feeling that the IOF that made the 7.62 SMLE is not the same IOF churning out the current junk - INSAS, .32 rev & pistol, .22 rev, 9mm pistol... etc. etc. All scrap!!! :evil:

Just the other day was chatting with a young army captain who also happens to be a sniper instructor and I asked him about the INSAS... he just made a wry face and refused to comment beyond the fact that in J&K the average chappie preferred to use the the AK series for combat use rather than our home grown "hi-tech" assault rifle... Why? He laughed and said, "Well, everyone likes to live as long as possible..."

Cheers!
Abhijeet

Posted: Sun Jun 01, 2008 9:49 am
by badshah0522
mundaire";p="44807 wrote: Why? He laughed and said, "Well, everyone likes to live as long as possible..."

Cheers!
Abhijeet
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