what does と and other kanjis stand for in this sentence?

Question

I was reading an article and learning new kanji. However, I am having hard time determining some grammatical structures and kanji from this sentence:

有坂銃{ありさかじゅう}とは、大日本帝國のボルトアクション方式の軍制式小銃の系列であり、それまでの村田銃系列の小銃を更新する為に1897年より製造が始まり、第二次世界大戦が終結する1945年まで製造された一連の小銃をさす

1. What does と stand for?
2. 方式 (Does it mean "model"? It says system, form or formula.)
3. 軍制式小銃の系列 (Does it mean military small rifle series?)
4. であり (Does it mean "have the quality of being" in this sentence?)

Answer 1

1. What does と stand for?

Please refer to Use of とは when there doesn't seem to be comparison.

2. 方式 (Does it mean "model"? It says system, form or formula.)

It's not a complicated word at all, but a bit roundabout if explained precisely using the English grammar. You can replace all ～方式の with "working by —", so that ボルトアクション方式の小銃 becomes "a rifle working by bolt action", but I guess you just say "a bolt action rifle" in natural English.

3. 軍制式小銃の系列 (Does it mean military small rifle series?)

• 軍: army, here means the Imperial Army
• 制式: a term that means, dead literally, armament catalog designation; or used as an adjective to mean "officially adopted"
• 小銃: rifle
• 系列: series

4. であり (Does it mean "have the quality of being" in this sentence?)

Please refer to Do I have a good grasp on the basics of what the continuative form is?

So,

大日本帝國のボルトアクション方式の軍制式小銃の系列であり

translates into

is a series of Imperial Japanese bolt action rifles adopted by the Army, and...