How Do They Know It's A Marlin?


September 15, 2004, 02:58 PM
You may have heard about the horrible beach killings in Northern California of two young college-age kids.

The San Francisco Chronicle has now reported in some detail that the weapon is a "Marlin .45"."

Chronicle Article (

How can they know the brand without solid evidence? Can ballistics show this, i.e., evidence of Marlin patented "micro groove" rifiling? If they've identified the bullet as a .45 slug. why not a .45 hand gun? How 'bout a .44 or .41?

I'm a Marlin owner and fan. Marlin only makes a lever action in .45 Colt. I can think of no less improbable weapon than a "Cowboy Action" style lever gun. The other suspect appears to be a Camp Rifle, long out of production and rare around here.

If you enjoyed reading about "How Do They Know It's A Marlin?" here in archive, you'll LOVE our community. Come join today for the full version!
September 15, 2004, 03:10 PM
Most of the cowboy guns don't have microgroove barrels anyway. Cowboy requires you to shoot raw lead and microgroove doesn't tend to do well with it. My guess is that they suspect a marlin camp carbine. Those are still fairly available used if you look in the right places.

September 15, 2004, 03:43 PM
Typically the most ballistically useful info comes from the number of grooves and the right or left hand twist of the barrel (found on the bullet) and the breech face imprint on the primer of a spent case. If they were able to recover the bullets and a case, then they could narrow down the list of potential firearms. Off hand I do not recall if Marlin uses a unique barrel profile, but I bet they do (for stuff able to shoot .45ACP).

September 15, 2004, 04:33 PM
What in the hell gun are they talking about??

They're making it sound like they can tell it's a Marlin .45; but they can't tell whether it's a camp gun (45acp) or an 1894 (45colt). How in the world could you tell it was a Marlin without even being able to tell which of these rounds it was???


Of course, the article shows enough basic lack of understanding of calibers and guns that there could well be a flat-out error in representing what LE is saying.


Mal H
September 15, 2004, 04:52 PM
They've given no details on the actual caliber. Folks seem to be fixed on .45 Colt or .45 ACP. Might be Marlin 450 or a 45/70. Both of those would easily lead forensics to determine if a Marlin rifle was used from the groove depth and twist rate.

September 15, 2004, 05:18 PM
Micro-Grove is patented IIRC, and is quite distinct even to the naked eye. If they found a .45 cal slug with micro-grove rifling, they're probably after an older model .45-70. I expect anything beyond ".45 caliber" would be too complex for the reporters to cope with.

September 15, 2004, 05:25 PM

Typically the type of weapon can be determined from the rate and direction of the rifling on the bullet. Unless reloading is involved, the type of bullet can show the caliber of the weapon.

For instance, a 230 FMJ bullet is pretty unique to the .45 ACP round. Most factory .45 Colt ammo uses a 250/255 grain lead flat pointed bullet.

And the biggest thing to remember in this particular matter:

What the SFran Chronicle knows is NOT what the investigators know. In other words, the newspaper account may not perfectly reflect the information contained in the investigative report.

I bet the investigators know what weapon was used.

September 15, 2004, 05:51 PM

The article states that the .45 caliber round in question "is the same as that used in .45-caliber pistols "

I'm not positive, but I think that rules out the .450 Marlin and .45-70. The only pistols that might fire these rounds, IIRC, would be Thompson-Center, which is pretty much beyond most reporters.

The fact that even the paper refers to lever-guns makes me think it might be the .45 Colt, since I don't think Marlin makes leverguns in .45ACP (does anyone?).

Then again, I don't think anyone makes semi-autos in .45 Colt.

Central question: What .45 caliber does Marlin make (or did make) both a semi and lever action rifle in?

September 15, 2004, 06:36 PM
It may not be in the internet edition, but in the paper this morning the picture with the article was of a police officer holding up a lever action rifle and what appeared to be a semi-auto rifle. My confusion is that Marlin makes a lever action in .45 Colt (not .45 ACP) and the Camp carbine was in .45 ACP (and not .45 Colt).

Here's the picture:

Marlin Lever Action and Semi-Auto (

Edit: The link is actually to a news video.

It's clear the police are talking about a Marlin 1894 and a Camp Carbine.

September 15, 2004, 07:24 PM

Are you telling me they can't tell the difference between a .45 Colt and a .45 ACP?! That's some high tech CSI work for you :rolleyes:

" were shot and killed by .45 caliber rifles manufactured by the Marlin company. One is fired by lever action, and the other is a semi-automatic."

And this makes it sound as though each victim was shot with a different rifle. One with a camp carbine in .45 ACP, the other by a levergun in .45 Colt. Or perhaps a suspect with one in each arm. Or two one-armed suspects.

September 15, 2004, 07:30 PM
I'm not positive, but I think that rules out the .450 Marlin and .45-70. The only pistols that might fire these rounds, IIRC, would be Thompson-Center, which is pretty much beyond most reporters.

The Magnum Research BFR also fires 45/70.

September 15, 2004, 08:49 PM
A number of companies load the same bullet in both .45 ACP and .45 Colt (e.g. the Speer Gold Dot hollowpoints). So, if the cops have recovered bullets that could be fired in either round, and which have rifling marks leading them to identify the gun as having either the earlier Micro-Groove or the later Ballard-type rifling that Marlin uses... QED!

However, I still don't like the idea of the police going from door to door, asking for rifles in these calibers to be handed over for testing. No way would they get mine without a properly executed search warrant, setting forth in detail its Constitutional limitations - and I would demand a signed receipt, giving details of the condition of the rifle(s), so that if they came back to me in any worse condition, I would have grounds to recover repair costs from the police.


September 15, 2004, 09:47 PM
Now, this:
Sonoma County sheriff's investigators said Tuesday that two Christian camp counselors found slain last month on an isolated beach near Jenner had probably been shot with a hunting rifle.(Empasis added.) makes me think they didn't get shot with a Camp Carbine.

Granted, they're pretty innocuos-looking, but I'd think they're just too "eeevil" by virtue of semi-operability (Mediaspeak for "rapid-fire".) and it's got "quick-change magazines?" (Oh my! :eek: )

Ignint and brain-damaged they may be, the media are slicj 'n fast to seeze on anything they can even SPECULATIVELY hold agains gun-owners.

On the other hand, this:

The .45-caliber ammunition used in the rifles is the same as that used in .45-caliber pistols and is made by a variety of manufacturers. The lever- action model ejects the spent cartridge and loads a new round during the cocking of the lever, just like the like old Winchester of cowboy movie fame. The semiautomatic model fires a bullet, ejects the spent casing and reloads a new round each time the trigger is pulled, Edmonds said. (Empasis added.) would certainly point right at the Camp Carbine, for reasons already mentioned.

1911's are usually .451-or-2 230-gr. fmj's with 5-groove 1-17" RH twist, which I believe the Carbine duplicates.

Marlin levers, the non-CAS ones, anyrate, run on .454 250-60 gr. copper-plated LSWCS in a 20-"V"-groove 1-20" LH twist Microgroove barrel. If it's a cowboy special, Marlin substitutes a standard 5-"square"-groove rifling pattern, but maintains the direction and rate-of-twist. I think.

Edit: .45-70's, and I think the .450 also, run on .458's. .45-70's are 405-gr. JSP's or 325-gr. 1/2-jacket HP"s. Rifling's 1-18" RH twist Microgroove, although regular Ballard rifling has lately become avaailble in response to CAS and hunting demand. The .450 runs 350-gr. JHP's that're also .458 diameter. If those folks got shot with either of those, compared to a Camp Carbine, I'd thiunk you'd know as soon as you saw 'em.

I'm inclined to think Newsguy knows nothing of specifics, and the cops might be playng a bit of public misdirection in hopes of the perp making a mistake.

Could be a clueless cop, also. Only Gun-nut, Brady-says-we're-DANGEROUS loose in the neighborhood-'cuz-we-eat-children hobbiests are expert enough to know the exact specifics of different forms of "Colt .45 ammo" and ".45 Colt ammo" at the drop of a few cryptic clues. Honest confusions happen.

But WE'DS ain't da perps dey lookin' fer.

And what're the chances Murdering Bastid A) knowing what we know, and B) carrying around a levergun indtead of a semi-auto .45?

September 16, 2004, 01:24 AM
45 LC and 45 ACP often use the same bullets.

I was confused about why the investigators would be looking for either a semiauto OR a lever action, because ejection is so different on those two actions. Then I realized that Marlin LA are unique, in that they use a side-ejection port. Are there similarities between Marlin auto extraction and ejection, and that of the lever action? (Marlin owners and 'smiths, please help)

Based on their uncertainty (and mine too, I guess), here is what I think they have:

Two very deformed, soft lead bullets (unjacketed?), with enough deformation that identification based solely on barrel grooves is impossible. The velocity needed to achieve such deformation/fragmentation might only be possible from a longer-than-handgun barrel. There is still enough evidence to conclude a Marlin barrel.

Obviously, no brass was found at the scene, since 45 LC and 45ACP are completely different.

They were both shot in the head. Do cranial shots cause more deformation with soft bullets?

Hey, look at that-No brass to conclusively identify the round. Whoever did this knew a thing or two about evidence gathering, and picked up after himself. Not the usual MO of a druggie or crazy.

Then again, maybe I'm completely wrong.

September 16, 2004, 08:18 AM
Head shot might deform an unjacketed lead bullet pretty well-it'd have to bash it's way through the skull (deformation #1, and if it didn't bash it's way out the other side (deformation #2) and into the ground (deformation #3), it could bang around inside the skull, deforming the entire time (not to metion making the brain into mush.)

Have to agree that the shooter must have picked up his brass, otherwise they'd know if it was a camp carbine or a levergun.

One thing I did find odd: this article ( states that Marlin only made about 10,000 leverguns in the right caliber, and 3,000 camp carbines...and yet they've taken and tested a few dozen guns just in that one county? 13,000 rifles, scattered about the whole country, and there's that many in one California county?

September 16, 2004, 10:34 AM
Well... they THINK it might have been a Marlin .45 rifle .... :rolleyes:

And the killers were driving a white box truck too - watch out for those! :p

If you enjoyed reading about "How Do They Know It's A Marlin?" here in archive, you'll LOVE our community. Come join today for the full version!