More noob questions

[brekneb]

People are probably beginning to recognize me by my sheerly noob questions. Oh well I have some more. I'm desperately noob.

Rimfire/Centerfire. From my understanding RF: primer is in base of cartridge. CF: primer is in individual separate component within the base. So
1 what makes CF more accurate?
2 what keeps the primer separate from the main charge in RF?
3 what is the primer itself? What type of compound?
4 what does the firing pin do to the primer upon striking it? (Does the pin basically cause the primer to detonate sheerly due to the impact force of the pin?)
5 so does the primer actually detonate or 'explode' or is it merely the contact of primer-to-powder charge which causes the ignition?

Iron sights. Adjusting point of aim shifts point of impact accordingly? (move rear sight left and POI is now shifted left) correct?

Pistol receivers. It's easy for me to understand a receiver on a shotgun or rifle but a auto pistol?
I'm guessing the receiver in a handgun is a singular component with the slide?
(It's just odd to try to get my mind wrapped around that one, since a rifle or shotgun receiver remains stationary--and therefore easy to imagine).

Oh yeah what exactly is within the inherent design of a firearm which delays the unlocking of the bolt lugs from the breech to allow the pressure to drop to a safe level prior to releasing? (Basically how does it delay until the pressure has dropped?)

Last one:
Recoil operation/blowback/gas operation, etc
What all the different types of cycling operations are there in the firearms world?
And in general reference (not too detailed or descriptive) as I understand it, recoil operation is typically a design in pistols where the barrel travels rearward with the bolt a slight distance until the bolt unlocks?--So what keeps the barrel locked into the slide preventing it from falling free? The bushing?
And so blowback is where the bolt is simply held shut by recoil spring pressure?--Is this only used in low caliber or no?
And gas operation I fairly well have understood. Doesn't the Desert Eagle incorporate a gas cylinder due to the sheer, massive cartridges it fires?

I think that's it. For now. I'm always wondering whether I'm posting too much at once.
Thanks as always.

 

[esheato]

Hi scoob,

what makes CF more accurate?

They're not necessarily more accurate. Match quality .22 RF is more than adequately accurate for its intended purpose. RF and CF primers have different intended uses...varying amounts of propellants to ignite, and very different size and weight projectiles to launch.

what keeps the primer separate from the main charge in RF?

It is inserted into the case as a liquid and it is spun into the outer edges of the case where it dries. Propellent is inserted into the case after the priming operation.

what is the primer itself? What type of compound?

I'd assume a mercury fulminate of some sort...(I'd confirm this before believing it).
Primer Article

what does the firing pin do to the primer upon striking it? (Does the pin basically cause the primer to detonate sheerly due to the impact force of the pin?)

Yes. The priming compound is crushed between the two opposing rims of the cartridge.

so does the primer actually detonate or 'explode' or is it merely the contact of primer-to-powder charge which causes the ignition?

Yes. The priming compound in RF or the primers in CF are the only things explosive about cartridges.

Iron sights. Adjusting point of aim shifts point of impact accordingly? (move rear sight left and POI is now shifted left) correct?

Yes. You always move the rear sight in the direction of bullet travel that you want.

Pistol receivers. It's easy for me to understand a receiver on a shotgun or rifle but a auto pistol?

While it's easy to separate actions and receivers in long guns the line becomes blurry when it comes to handguns. The nomenclature also changes. When referencing autoloaders, you have two parts: the slide and the frame. In reference to revolvers, you have the frame, barrel, and cylinder. When you say, "the action" in reference to a handgun, you're talking about the guts of the gun. The working parts that allows it to fire. For example. : "I just got it back from the smith, I had an action job done."

Types of Actions

Hope this helps.

Ed

 

[Stickjockey]

what is the primer itself? What type of compound?

This from CCI's website:

Primer Evolution
The explosive mix in the earliest primers was mercury fulminate. The development of the fulminate priming virtually ended the flintlock period. Percussion caps—small, soft metal cups with a pellet of fulminate—replaced the flint in muzzle-loading firearms. Extremely reliable for the period, fulminate primers ruled the industry well into the fixed-cartridge era. However, it was the cartridge case that ended fulminate's hold.

The mercury residue in these primers attacked cartridge brass and made it brittle, resulting in case failures. Those who wanted to reload the case needed help. This need saw the development of primers whose initiator was potassium chlorate. This chemical, although its residue was corrosive if left in the gun or case, did not adversely affect the brass if the cases were rinsed after firing. Chlorate primers were developed in the black powder period, when firearms had to be cleaned with water or rust away. When non-corrosive smokeless propellants began to replace black powder in the 1890's, shooters still had to use water-based cleaners to prevent the chlorate residue from rusting their firearms.

This situation was remedied in the late 1920's when lead styphnate priming was developed. This primary explosive left no corrosive residue, and meant that shooters no longer had to wash their guns. Today, styphnate priming is nearly universal.

what makes CF more accurate?

The primary factor limiting rimfire's performance in larger cartriges is the required thinness of the material at the back of the case for rimfire to be reliable. This limits the case's ability to handle pressures, thus limiting the muzzle velocity of the round. For how it's used, rimfire can be every bit as accurate as CF.

 

[Majic]

Unless it's an antique handgun the easiest way for you to tell the receiver of a handgun is to look for the serial number. The serial number will always be on the receiver. For a revolver it's the frame minus the barrel, cylinder, yoke/crane and the semi-auto it's the frame minus the slide.

 

[Lupinus]

1 what makes CF more accurate?

Isn't nessisarily more accurate but it can hold up to stronger loads. Also Center fire can be reloaded since the actual case isn't damaged and the primer can be removed for a new one. Rimfire the base of the case is crushed making reloading impossible. Also to crush it can only be so thick which makes it not as good for stronger calibers. But one of the main factors that made center fire better then rimfire was the fact it is reloadable.

2 what keeps the primer separate from the main charge in RF?

The primer compound is placed inside the rim of the base, when it dries it keeps the powder from mixing.

3 what is the primer itself? What type of compound?

Im not sure what the actual compound is but basicly it is a compound which when hit by a fireing pin and crushed exploads. The spark from the explosion goes through a hole (called a vent) into the case and ignites the powder charge.

4 what does the firing pin do to the primer upon striking it? (Does the pin basically cause the primer to detonate sheerly due to the impact force of the pin?)

Basicly it crushes the compound causing it to expload.

5 so does the primer actually detonate or 'explode' or is it merely the contact of primer-to-powder charge which causes the ignition?

The compound literaly explaods which in turn ignites the powder charge.

Iron sights. Adjusting point of aim shifts point of impact accordingly? (move rear sight left and POI is now shifted left) correct?

Point of aim basicly means where the sights go is where it will hit. Some firearms though are set up slightly different. Such as six o'clock, which means you would aim just low of where you want the buller to actually hit.

I'm guessing the receiver in a handgun is a singular component with the slide?

The reciever on an auto is the gun itself minus the slide, barrel, and magazine.

What all the different types of cycling operations are there in the firearms world?

The relate to what cycles the action. Recoil operation uses the force of the recoil. Gas operation uses some gas funneled off through a port into a cylinder and usualy a piston to cycle the action. Blowback uses the force of preasure within the chamber to literaly blow it back. Delayed blow back is the same thing but uses a spring or something to delay it blowing back.

 

[ralphie98]

Wow, these are very informative posts to questions I would have never thought to ask. I'm a bit of a newbie myself so this is fun stuff to learn.

keep the good info coming

 

[RVSinOK]

I agree! I have learned so much here, and it just keeps coming. Thanks for asking, Scoob_i_e!

 

[jsalcedo]

Buy books by Ian V. Hogg


You will learn more than you ever wanted to know about armor, weapons and ammunition.


Used book stores and Ebay are good places to start.

 

[brekneb]

WOW! As always the information factor is high here. So is the willingness to help out.
My questions have been quite thouroughly answered here. I have a clear idea on what I was wondering about now.
And yeah, I would agree with a couple of other people who posted on this thread that it seems sometimes more information is gleamed when you check over someone else's posts.
Plus, as I've learned, going back over "beginner" things--even for the pros--is not a bad thing at all. Always can learn something unexpected you thought you knew everything about.

thanks esheato, stickjockey, majic, lupinus, ralphie98, rvsinok, jsalcedo
and everyone else who have answered other questions from time to time.

 

[esheato]

No problem. I'm glad to help.

We'll be here if you have other questions. Don't be shy.

Ed